ci: rename linux-TEST-vars job

The "linux-TEST-vars" job exercises Git with a bunch of non-default
options enabled. The name of that job makes you want to cry though due
to the weird upper-casing and because it doesn't really tell you what it
even intends to do.

Rename the job to "linux-feature-testbed" instead.

Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

.github/workflows/main.yml

@@ -408,7 +408,7 @@ jobs:
         - jobname: linux-reftable
           image: ubuntu:rolling
           cc: clang
-        - jobname: linux-TEST-vars
+        - jobname: linux-feature-testbed
           image: ubuntu:20.04
           cc: gcc
           cc_package: gcc-8

.gitlab-ci.yml

@@ -42,7 +42,7 @@ test:linux:
       - jobname: linux-reftable
         image: ubuntu:rolling
         CC: clang
-      - jobname: linux-TEST-vars
+      - jobname: linux-feature-testbed
         image: ubuntu:20.04
         CC: gcc
         CC_PACKAGE: gcc-8

ci/run-build-and-tests.sh

@@ -22,7 +22,7 @@ fedora-breaking-changes-meson|linux-breaking-changes)
 	export WITH_BREAKING_CHANGES=YesPlease
 	MESONFLAGS="$MESONFLAGS -Dbreaking_changes=true"
 	;;
-linux-TEST-vars)
+linux-feature-testbed)
 	export OPENSSL_SHA1_UNSAFE=YesPlease
 	export GIT_TEST_SPLIT_INDEX=yes
 	export GIT_TEST_FULL_IN_PACK_ARRAY=true