Merge branch 'docs-change-to-sentence-case' into 'master'

Change to sentence case

See merge request gitlab-org/gitlab-ee!7095

doc/integration/jira_development_panel.md

-# GitLab JIRA Development Panel integration **[PREMIUM]**
+# GitLab JIRA development panel integration **[PREMIUM]**
 
 > [Introduced][ee-2381] in [GitLab Premium][eep] 10.0.