Fix InstallCodeMirror export

[jordojordo]

Summary

When running an extension locally in the dev environment with the latest Vue3 changes that uses the CodeMirror plugin, you will get an warning in the console:

 warning  in ./node_modules/@rancher/shell/initialize/install-plugins.js

export 'InstallCodemirro' (imported as 'InstallCodemirro') was not found in 'codemirror-editor-vue3' (possible exports: CodeMirror, GlobalCmComponent, InstallCodeMirror, VueCodemirror, createLinkMark, createLog, createLogMark, createTitle, default, getLinkMarks, getLocalTime, getLogMark, logErrorType)

Occurred changes and/or fixed issues

This fixes the import and export for InstallCodeMirror.

Technical notes summary

Areas or cases that should be tested

An extension using the CodeMirror plugin.

Areas which could experience regressions

Screenshot/Video

Checklist

• The PR is linked to an issue and the linked issue has a Milestone, or no issue is needed
• The PR has a Milestone
• The PR template has been filled out
• The PR has been self reviewed
• The PR has a reviewer assigned
• The PR has automated tests or clear instructions for manual tests and the linked issue has appropriate QA labels, or tests are not needed
• The PR has reviewed with UX and tested in light and dark mode, or there are no UX changes