Revert "Revert setting GIT_COMITTER_NAME/EMAIL. It doesn't do anything."

This reverts commit 9b01428dde1d2476f177c2437bdd60063ec8147c.

autobuild.py

@@ -481,6 +481,11 @@ def get_build_environ() -> Dict[str, str]:
         packager_ref += "/" + environ["GITHUB_SHA"][:8] + "/" + environ["GITHUB_RUN_ID"]
     environ["PACKAGER"] = f"CI ({packager_ref})"
 
+    # XXX: Some PKGBUILDs use "git am" which requires a committer to be
+    # configured, or it will fail. So do it here.
+    environ["GIT_COMMITTER_NAME"] = Config.MAIN_REPO
+    environ["GIT_COMMITTER_EMAIL"] = "ci@msys2.org"
+
     return environ