Remove the "-r" option in calling gap in the pexpect interface #27878
Description
Currently the pexpect interface to gap call gap with the "-r" option.
From sage/interfaces/gap.py
gap_cmd = "gap -r"
This is a remnant of gap 4.8 and under where it enabled gap to be started in a quieter mode if I am not mistaken. There is no visible effect in starting gap with or without "-r" in gap 4.10 and over.
fbissey@moonloop ~ $ gap
┌───────┐ GAP 4.10.1 of 23-Feb-2019
│ GAP │ https://www.gap-system.org
└───────┘ Architecture: amd64
Configuration: gmp 6.1.2, readline
Loading the library and packages ...
Packages: AClib 1.3.1, Alnuth 3.1.0, AtlasRep 1.5.1, AutoDoc 2019.02.22, AutPGrp 1.10, CRISP 1.4.4, Cryst 4.1.18, CrystCat 1.1.8, CTblLib 1.2.2, FactInt 1.6.2, FGA 1.4.0,
GAPDoc 1.6.2, IO 4.5.4, IRREDSOL 1.4, LAGUNA 3.9.2, Polenta 1.3.8, Polycyclic 2.14, PrimGrp 3.3.2, RadiRoot 2.8, ResClasses 4.7.1, SmallGrp 1.3, Sophus 1.24,
TomLib 1.2.7, TransGrp 2.0.4, utils 0.61
Try '??help' for help. See also '?copyright', '?cite' and '?authors'
gap>
fbissey@moonloop ~ $ gap -r
┌───────┐ GAP 4.10.1 of 23-Feb-2019
│ GAP │ https://www.gap-system.org
└───────┘ Architecture: amd64
Configuration: gmp 6.1.2, readline
Loading the library and packages ...
Packages: AClib 1.3.1, Alnuth 3.1.0, AtlasRep 1.5.1, AutoDoc 2019.02.22, AutPGrp 1.10, CRISP 1.4.4, Cryst 4.1.18, CrystCat 1.1.8, CTblLib 1.2.2, FactInt 1.6.2, FGA 1.4.0,
GAPDoc 1.6.2, IO 4.5.4, IRREDSOL 1.4, LAGUNA 3.9.2, Polenta 1.3.8, Polycyclic 2.14, PrimGrp 3.3.2, RadiRoot 2.8, ResClasses 4.7.1, SmallGrp 1.3, Sophus 1.24,
TomLib 1.2.7, TransGrp 2.0.4, utils 0.61
Try '??help' for help. See also '?copyright', '?cite' and '?authors'
gap>
The only effect is more subtle. ~/.gap and its equivalent on non linux system is not added to the list of paths where gap looks for packages. This means in turn that the option ignore_dot_gap in the function all_installed_packages (in sage/tests/gap_packages.py) is meaningless when a pexpect gap instance is selected. And a doctest introduced in #27681 will fail if you have something in ~/.gap.
Component: interfaces
Author: François Bissey
Branch/Commit: u/fbissey/gap_r @ 474b365
Reviewer: Steven Trogdon
Issue created by migration from https://trac.sagemath.org/ticket/27878