When using CodeMirror, search patterns have literal highlighting and hovers on page load

Created by: lguychard

• Sourcegraph version: Cloud
• Platform information: Safari 15.4

⚠️ CodeMirror feature flag turned on ("editor": "codemirror6")

Steps to reproduce:

1. Navigate to this link
2. Witness the query's patternType is regex, and the regex toggle state is correct.
3. Witness the pattern, @bazel_tools.*javac, has literal syntax highlighting and hovers

4. Toggle regex off, then on again.
5. Witness the pattern now has correct highlighting + hovers.

Expected behavior:

Pattern is correctly highlighted as regex on page load.

Actual behavior:

Pattern is incorrectly highlighted on page load when using "editor": "codemirror6"