restrict scheduled bundle releases to the latest four versions (#179)

.github/workflows/scheduled_releases.yml

@@ -29,6 +29,6 @@ jobs:
       matrix:
        # we support the trailing four versions plus the latest pre-release
        # and the upcoming version's pre-release.
-        version: ["1.1.0", "1.2.0", "1.3.0", "1.4.0", "1.5.0", "1.6.0b2", "1.6.0", "1.7.0rc1", "1.7.0", "1.8.0b1", "1.8.0"]
+        version: ["1.5.0", "1.6.0", "1.7.0", "1.8.0b1", "1.8.0"]
     with:
       version_number: ${{ matrix.version }}