(DOCSP-36966) Add a PR template to this repo (#883)

* (DOCSP-36966) Add a PR template to this repo

* Edits per review

Author: JuliaMongo

.github/pull-request-template.md

@@ -0,0 +1,18 @@
+<!-- Add a description of your PR here (optional) -->
+
+- [DOCSP-number](https://jira.mongodb.org/browse/)
+- [STAGING](paste the link to staging here)
+
+- [LATEST BUILD LOG](paste the build here)
+
+### Self-Review Checklist
+
+- [ ] Check that the submodule pulled in the right changes (if applicable).
+- [ ] [Define](https://wiki.corp.mongodb.com/display/DE/Taxonomy+tagging+instructions) taxonomy [values](https://wiki.corp.mongodb.com/display/DE/Docs+Taxonomy) at top of page.
+- [ ] Add genre facets (tutorial or reference), as in this [example PR](https://github.com/10gen/cloud-docs/pull/5042).
+- [ ] Add programmingLanguage (if necessary).
+- [ ] Add meta keywords (if necessary).
+- [ ] Resolve any new warnings or errors in the build.
+- [ ] Proofread for spelling and grammatical errors.
+- [ ] Check staging for rendering issues.
+- [ ] Confirm links are working.