meson: Fix version script

Apparently, the `|` has a higher priority…

meson.build

@@ -1813,8 +1813,8 @@ version_tag = get_option('version-tag')
 if version_tag == '' and git.found() and fs.exists(project_source_root / '.git')
         # If the working tree has no tags (CI builds), the first git-describe will fail
         # and we fall back to project_version-commitid instead.
-        version_cmd = '''git -C "$1" describe --abbrev=7 --dirty=^ 2>/dev/null ||
-                         echo "$2-$(git -C "$1" describe --always --abbrev=7)" |
+        version_cmd = '''(git -C "$1" describe --abbrev=7 --dirty=^ 2>/dev/null ||
+                          echo "$2-$(git -C "$1" describe --always --abbrev=7)") |
                          sed 's/^v//; s/-rc/~rc/' '''
 else
         version_cmd = '''echo "$2" '''