CompatHelper: bump compat for CommonMark to 0.9, (keep existing compat) (#275)

Co-authored-by: CompatHelper Julia <[email protected]>

Author: github-actions[bot]

Project.toml

@@ -29,7 +29,7 @@ YAML = "ddb6d928-2868-570f-bddf-ab3f9cf99eb6"
 [compat]
 BSON = "0.3"
 Base64 = "1.6"
-CommonMark = "0.8"
+CommonMark = "0.8, 0.9"
 Compat = "4"
 Dates = "1.6"
 IOCapture = "0.2"