Swagger UI 3.20.7 Released!

Interface changes: none.

Changelog:

• improvement: generate non-smart Markdown quotes (via #5162)
• improvement(docker): smaller images via no-cache option (via #5157)
• fix: coerce multipart initial property values to string (via #5166)
• fix: gracefully handle malformed global tags array in taggedOperations selector (via #5159)
• fix: don't trigger url remote document load if urls is provided (via #5161)
• housekeeping: corresponding changes for swagger-api/swagger-editor#1935 (via #5170)
• housekeeping: losslessly crush PNG images with pingo (via #5158)