Change Pajamas Danger rule to fail on migrated components

What does this MR do?

Improves the Danger rule to accommodate both blocking and non-blocking failures. Blocking for components that have been migrated already and non-blocking for those that are not migrated yet. The list of blocking components is currently empty, the expectation is that the components will be moved from PATTERNS to BLOCKING_PATTERNS as the migration progresses.

Tested in !44366 (closed)

Second iteration of gitlab-com/www-gitlab-com#8596 (closed)

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content