Revert "Disable darmwin-x86" - the x86 mac mini has a new home

This reverts commit 79fa3c0b.

.gitlab-ci.yml

@@ -73,13 +73,13 @@ include:
       tagname: 'macOS-aarch64'
       gnu_make: 'make'
       build_flags: 'RELEASE=1'
-#  - local: '.gitlab-ci-unix.yml'
-#    inputs:
-#      os: 'darwin-x86'
-#      platform: 'x86'
-#      tagname: 'macOS-x86'
-#      gnu_make: 'make'
-#      build_flags: 'CC="ccache cc" CXX="ccache c++" RELEASE=1'
+  - local: '.gitlab-ci-unix.yml'
+    inputs:
+      os: 'darwin-x86'
+      platform: 'x86'
+      tagname: 'macOS-x86'
+      gnu_make: 'make'
+      build_flags: 'CC="ccache cc" CXX="ccache c++" RELEASE=1'
 
 smoketest-jsexec-linux:
   tags: [Linux]