The -Zno-landing-pads flag is longer supported: rust-lang/rust@bf45975.

I've tried specifying -Cpanic=abort but that failed with error:

error: building tests with panic=abort is not supported without `-Zpanic_abort_tests`

Additionally adding -Zpanic_abort_tests still failed but at a later point:

error: the crate `libnewsboat` is compiled with the panic strategy `abort` which is incompatible with this crate's strategy of `unwind`

I don't really know why we specify -Zno-landing-pads in our Test Coverage job so I have no idea if we can just drop it.