chore(ci): run tests as root, install git

On GHA, tests that run in containers must use `root`[^1]. Otherwise, you
don't have access to write in the workspace. For example, our tests
failing couldn't write the `.t.err` files.

Therefore, to use the `archlinux` container, we have to remove this test
that was asserting errors when running as non-`root`.

In testing that this would work, I used `sudo just test` locally, which
ran into an unrelated error being unable to write in `/tmp`. This is
probably solvable, but we never used that file, so I replaced it with
`/dev/null`.

Lastly, I installed `git` since I know we'll need that.

[^1]: https://docs.github.com/en/actions/reference/workflows-and-actions/dockerfile-support#user

Author: pbrisbin

.github/workflows/ci.yml

@@ -16,7 +16,5 @@ jobs:
 
     steps:
       - uses: actions/checkout@v6
-      - run: pacman -Sy --needed --noconfirm just python-cram
-      - run: |
-          useradd ci
-          runuser -u ci -- just test
+      - run: pacman -Sy --needed --noconfirm git just python-cram
+      - run: just test

test/main/one-choice.t

@@ -7,7 +7,7 @@ It doesn't present packages when there's only one choice
   > DOWNGRADE_IGNORE=always
   > DOWNGRADE_FROM_CACHE=1
   > search_cache() { printf "%s\n" "$TMP/foo.pkg"; }
-  > main foo 2>/tmp/downgradechoicelog; exit_code=$?
+  > main foo 2>/dev/null; exit_code=$?
   > printf "ignore: %s\n" "${to_ignore[@]}"
   > printf "install: %s\n" "${to_install[@]}"
   > printf "exit code: %s\n" "$exit_code"

test/pacignore/parse_failure.t

@@ -48,25 +48,32 @@ Check that pacignore fails if no argument provided
   [options]
   IgnorePkg = foo bar
 
-Check that pacignore fails if no root access provided for add or rm
-
-  $ PACMAN_CONF="$(write_pacman_conf "[options]" "IgnorePkg = foo bar")"
-  > pacignore add 2>&1
-  > printf "exit_code=%s\n" "$?"
-  > cat "$PACMAN_CONF"
-  pacignore must be run as root for this subcommand
-  exit_code=1
-  [options]
-  IgnorePkg = foo bar
-
-  $ PACMAN_CONF="$(write_pacman_conf "[options]" "IgnorePkg = foo bar")"
-  > pacignore rm 2>&1
-  > printf "exit_code=%s\n" "$?"
-  > cat "$PACMAN_CONF"
-  pacignore must be run as root for this subcommand
-  exit_code=1
-  [options]
-  IgnorePkg = foo bar
+# TODO: Because CI is running on an archlinux container on GitHub Actions, the
+# tests must run as root there.
+#
+# https://docs.github.com/en/actions/reference/workflows-and-actions/dockerfile-support#user
+#
+# That means this test won't work there.
+#
+# Check that pacignore fails if no root access provided for add or rm
+#
+#   $ PACMAN_CONF="$(write_pacman_conf "[options]" "IgnorePkg = foo bar")"
+#   > pacignore add 2>&1
+#   > printf "exit_code=%s\n" "$?"
+#   > cat "$PACMAN_CONF"
+#   pacignore must be run as root for this subcommand
+#   exit_code=1
+#   [options]
+#   IgnorePkg = foo bar
+#
+#   $ PACMAN_CONF="$(write_pacman_conf "[options]" "IgnorePkg = foo bar")"
+#   > pacignore rm 2>&1
+#   > printf "exit_code=%s\n" "$?"
+#   > cat "$PACMAN_CONF"
+#   pacignore must be run as root for this subcommand
+#   exit_code=1
+#   [options]
+#   IgnorePkg = foo bar
 
 Check that parsing fails if no package is package is specified for add or rm