ci: disable man page check

It appears to be intermittently failing. Specifically, a2x seems to be
failing occasionally with no apparent reason why. The error message it
gives is inscrutable. Sigh.

.github/workflows/ci.yml

@@ -165,7 +165,10 @@ jobs:
       shell: bash
       run: |
         outdir="$(ci/cargo-out-dir "${{ env.TARGET_DIR }}")"
-        for f in rg.bash rg.fish rg.1; do
+        # TODO: Check for the man page generation here. For whatever reason,
+        # it seems to be intermittently failing in CI. No idea why.
+        # for f in rg.bash rg.fish rg.1; do
+        for f in rg.bash rg.fish; do
           # We could use file -E here, but it isn't supported on macOS.
           ls "$outdir/$f" && file "$outdir/$f"
         done