ci(macos): skip the git p4 tests

Historically, the macOS jobs have always been among the longest-running
ones, and recently the `git p4` tests became another liability: They
started to fail much more often (maybe as of the switch away from the
`macos-13` pool?), requiring re-runs of the jobs that already were
responsible for long CI build times.

Of the 35 test scripts that exercise `git p4`, 32 are actually run on
macOS (3 are skipped for reasons like case-sensitivee filesystem), and
they take an accumulated runtime of over half an hour.

Furthermore, the `git p4` command is not really affected by Git for
Windows' patches, at least not as far as macOS is concerned, therefore
it is not only causing developer friction to have these long-running,
frequently failing tests, it is also quite wasteful: There has not been
a single instance so far where any `git p4` test failure in Git for
Windows had demonstrated an actionable bug.

While upstream Git is confident to have addressed the flakiness of the
`git p4` tests via ffff0bb (Use Perforce arm64 binary on macOS CI
jobs, 2025-11-16) (which got slipped in at the 11th hour into the
v2.52.0 release, fast-tracked without ever hitting `seen` even after
-rc2 was released), I am not quite so confident, and besides, the
runtime penalty of running those tests in Git for Windows' CI runs is
still a worrisome burden.

So let's just disable those tests in the CI runs, at least on macOS.

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

ci/install-dependencies.sh

@@ -108,11 +108,12 @@ macos-*)
 	# brew install gnu-time
 	brew link --force gettext
 
-	mkdir -p "$CUSTOM_PATH"
-	wget -q "$P4WHENCE/bin.macosx12arm64/helix-core-server.tgz" &&
-	tar -xf helix-core-server.tgz -C "$CUSTOM_PATH" p4 p4d &&
-	sudo xattr -d com.apple.quarantine "$CUSTOM_PATH/p4" "$CUSTOM_PATH/p4d" 2>/dev/null || true
-	rm helix-core-server.tgz
+	# Uncomment this block if you want to run `git p4` tests:
+	# mkdir -p "$CUSTOM_PATH"
+	# wget -q "$P4WHENCE/bin.macosx12arm64/helix-core-server.tgz" &&
+	# tar -xf helix-core-server.tgz -C "$CUSTOM_PATH" p4 p4d &&
+	# sudo xattr -d com.apple.quarantine "$CUSTOM_PATH/p4" "$CUSTOM_PATH/p4d" 2>/dev/null || true
+	# rm helix-core-server.tgz
 
 	case "$jobname" in
 	osx-meson)