fix(mosaic): serialize credential lifecycle mutations

packages/mosaic/framework/tools/git/test-git-credential-mosaic.sh

@@ -16,6 +16,7 @@
 # NEVER reads real secrets or touches the real ~/.config/mosaic/secrets.
 
 set -euo pipefail
+umask 077
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 WORK_DIR="${MOSAIC_TEST_WORK_DIR:-$PWD/.mosaic-test-work/git-credential-mosaic}"
@@ -35,6 +36,7 @@ mkdir -p "$FAKE_HOME/.config/mosaic/secrets/gitea-tokens" \
 
 cp "$SCRIPT_DIR/git-credential-mosaic" "$HELPER"
 cp "$SCRIPT_DIR/resolve-credential-envelope.py" "$FAKE_HOME/.config/mosaic/tools/git/resolve-credential-envelope.py"
+cp "$SCRIPT_DIR/resolve-legacy-token.py" "$FAKE_HOME/.config/mosaic/tools/git/resolve-legacy-token.py"
 chmod +x "$HELPER"
 
 git -C "$REPO_DIR" init -q