Downgrade mac-os to version 12

Signed-off-by: Steve Pham <[email protected]>

.github/workflows/build-package.yaml

@@ -40,7 +40,7 @@ jobs:
               OS_RUNNER="windows-latest" # This is bundled with VS2022
               ;;
             darwin)
-              OS_RUNNER="macos-latest"
+              OS_RUNNER="macos-12"
               ;;
             *)
               OS_RUNNER="windows-latest" # default

package-system/python/darwin_x64/open3d_python.patch

@@ -103,25 +103,4 @@ index 8f33537..dad3d0c 100755
 +    return
 
      rsrcDir = os.path.join(pkgroot, 'Resources')
-
-diff --git a/Doc/requirements.txt b/Doc/requirements.txt
-index f43ce2c..2578393 100644
---- a/Doc/requirements.txt
-+++ b/Doc/requirements.txt
-@@ -3,13 +3,13 @@
- # Sphinx version is pinned so that new versions that introduce new warnings
- # won't suddenly cause build failures. Updating the version is fine as long
- # as no warnings are raised by doing so.
--sphinx==3.4.3
-+sphinx
- # Docutils version is pinned to a version compatible with Sphinx
- # version <3.5.4. It can be removed after bumping Sphinx version to at
- # least 3.5.4.
--docutils==0.17.1
-+docutils
- # Jinja version is pinned to a version compatible with Sphinx version <4.5.
--jinja2==3.0.3
-+jinja2
-
- blurb