feat: add PR template and dependabot workflow;

Author: WenjieDu

.github/PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,27 @@
+<!-- 🚨Please create your PR to merge code from your branch to `dev` branch here, rather than `main`. -->
+
+# What does this PR do?
+
+<!--
+Congrats! You've made it this far! You're not quite done yet though.
+
+Once merged, your PR is going to appear in the release notes with the title you set, so make sure it's a great title that fully reflects the extent of your awesome contribution 😉.
+
+Then, please replace this with a description of the change and which issue is fixed (if applicable). Please also include relevant motivation and context. List any dependencies (if any) that are required for this change.
+
+Once you're done, I will review your PR shortly. I may suggest changes to make the code even better 🤝.
+-->
+
+<!-- Remove if not applicable -->
+
+Fixing # (issue)
+
+
+## Before submitting
+
+<!-- You can remove checks that are not relevant to this PR. -->
+
+- [ ] This PR is made to fix a typo or improve the docs (you can dismiss the other checks if this is the case).
+- [ ] Was this discussed/approved via a GitHub issue? Please add a link to it if that's the case.
+- [ ] I have commented my code, particularly in hard-to-understand areas.
+- [ ] I have written necessary tests and already run them locally.

.github/dependabot.yml

@@ -0,0 +1,15 @@
+version: 2
+updates:
+  # Python Dependencies
+  - package-ecosystem: "pip"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+    open-pull-requests-limit: 5
+
+  # GitHub Actions
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+    open-pull-requests-limit: 5