v390

Merge pull request #2329 from alphagov/dependabot/npm_and_yarn/mermai…

v389

Merge pull request #2333 from alphagov/dependabot/bundler/google-prot…

v388

Merge pull request #2341 from alphagov/dependabot/bundler/aws-sdk-s3-…

v387

Merge pull request #2345 from alphagov/fix-flakey-integration-tests

Fix integration tests

v386

Merge pull request #2324 from alphagov/dependabot/npm_and_yarn/postcs…

v384

Merge pull request #2322 from alphagov/dependabot/npm_and_yarn/expres…

v383

Merge pull request #2328 from alphagov/448-implement-sub-navigation-p…

v382

Merge pull request #2332 from alphagov/remove-pollyfills

Remove require for polyfills closest as its no longer available

v381

Merge pull request #2326 from alphagov/389_Document-summary_Edit-page

389 document summary edit page

v380

Merge pull request #2327 from alphagov/fix-metrics

require prometheus client libs in mail_fetcher