Building `pgroll` now requires a functioning C toolchain on each
platform we aim to support, due to taking a dependency on
[pg_query_go](https://github.com/pganalyze/pg_query_go) for the
`sql2pgroll` package:
[pg_query_go](https://github.com/pganalyze/pg_query_go) requires
`CGO_ENABLED` to build.

This PR adds a new `cross-build` job in the CI workflow to build
`pgroll` binaries for each of our supported platforms:

* `linux/amd64`
* `linux/arm64`
* `darwin/amd64`
* `darwin/arm64`
* `windows/amd64`

The job runs in a
[goreleaser/goreleaser-cross](https://github.com/goreleaser/goreleaser-cross)
container in order to have access to a functioning C toolchain for each
of the above platforms. The `builds` section of the`.goreleaser.yaml`
config file is extended with an `overrides` section to configure the C
compiler for each platform build:

```yaml
      - goos: windows
        goarch: amd64
        env:
          - CC=x86_64-w64-mingw32-gcc
          - CGO_LDFLAGS=-lssp -static
      - goos: linux
        goarch: amd64
        env:
          - CC=x86_64-linux-gnu-gcc
      - goos: linux
        goarch: arm64
        env:
          - CC=aarch64-linux-gnu-gcc
      - goos: darwin
        goarch: amd64
        env:
          - CC=o64-clang
      - goos: darwin
        goarch: arm64
        env:
          - CC=oa64-clang
```

The values for the `CC` env var set the C compiler to use for each
OS/Arch target and are taken from the [goreleaser-cross
docs](https://github.com/goreleaser/goreleaser-cross?tab=readme-ov-file#supported-toolchainsplatforms).
The Windows build requires extra linker flags:

```
CGO_LDFLAGS=-lssp -static
```

due to having to link to the libssp stack-protection library and
statically link to avoid the runtime dependency on that library.

The job runs in a `surjection/goreleaser-cross:v1.23-v2.4.8` container,
which is NOT an official
[goreleaser/goreleaser-cross](https://hub.docker.com/r/goreleaser/goreleaser-cross/tags)
image. This image was built with this `Dockerfile`:

```dockerfile
FROM goreleaser/goreleaser-cross:v1.23-v2.4.4

WORKDIR /tmp

RUN wget https://github.com/goreleaser/goreleaser/releases/download/v2.4.8/goreleaser_Linux_x86_64.tar.gz \
  && tar -xvzf goreleaser_Linux_x86_64.tar.gz \
  && mv goreleaser /usr/bin/goreleaser

WORKDIR /
```

ie it installs the latest version Goreleaser `2.4.8` into the most
recent `goreleaser/goreleaser-cross` image. Once a
`goreleaser/goreleaser-cross` image using `goreleaser` `2.4.8` is
released we can switch back to the official images. Version `2.4.8` is
required due to a bug in earlier `goreleaser` versions that prevents the
`overrides` section in the `.goreleaser.yaml` file from working
(goreleaser/goreleaser#5298).

A `.zip` file containing the binaries for each supported platform is
uploaded as an artifact at the end of the job.

Stop using the custom image that was built as part of #525 and use an
offcial `gorelaser-cross` image instead. The image is used as the
container in which to build the project for multiple platforms. The
image provides C toolchains for all the platforms supported by `pgroll`.

The official image now uses `goreleaser` `v2.4.8` which contains the fix
for the bug (goreleaser/goreleaser#5298) that we
  were using the custom image to work around.

…uilds (#604)

Stop using the custom `goreleaser-cross` image that was built as part of
#525 and use an official `gorelaser-cross` image instead. The image is
used as the container in which to build the project for multiple
platforms. The image provides C toolchains for all the platforms
supported by `pgroll`.

The official image now uses `goreleaser` `v2.4.8` which contains the fix
for the bug (goreleaser/goreleaser#5298) that we
were using the custom image to work around.

Stop using the custom `goreleaser-cross` image that was built as part of
used as the container in which to build the project for multiple
platforms. The image provides C toolchains for all the platforms
supported by `pgroll`.

The official image now uses `goreleaser` `v2.4.8` which contains the fix
for the bug (goreleaser/goreleaser#5298) that we
were using the custom image to work around.

Stop using the custom `goreleaser-cross` image that was built as part of
used as the container in which to build the project for multiple
platforms. The image provides C toolchains for all the platforms
supported by `pgroll`.

The official image now uses `goreleaser` `v2.4.8` which contains the fix
for the bug (goreleaser/goreleaser#5298) that we
were using the custom image to work around.

Stop using the custom `goreleaser-cross` image that was built as part of
used as the container in which to build the project for multiple
platforms. The image provides C toolchains for all the platforms
supported by `pgroll`.

The official image now uses `goreleaser` `v2.4.8` which contains the fix
for the bug (goreleaser/goreleaser#5298) that we
were using the custom image to work around.

Follow up to #604 that updated the image elsewhere in the workflow but
forgot to update this one.