Add accessibility issue template #3464 (#3465)

.github/ISSUE_TEMPLATE/accessibility.md

@@ -0,0 +1,36 @@
+---
+name: Accessibility
+about: Report an accessibility issue
+title: ''
+labels: accessibility general
+assignees: ''
+
+---
+
+### URL
+
+
+### Issues
+
+
+### Severity
+
+
+### WCAG Conformance level (A, AA, AAA)
+
+
+### User impact
+
+
+### Recommended fix
+
+
+### Acceptance criteria
+- [ ] I can successfully use this feature with Voice Over in Safari.
+- [ ] I have checked this feature using one of the following browser extensions and confirmed that it does not add any level A or level AA issues:
+    * axe dev tools
+    * Lighthouse
+    * Wave
+- [ ] ...
+
+### Notes