Add workflow to add reviewers to PR (#34)

* Add workflow to add reviewers to PR

* Enable self assign to PR

Author: kentaro-m

.github/auto_assign.yml

@@ -0,0 +1,18 @@
+# Set to true to add reviewers to pull requests
+addReviewers: false
+
+# Set to true to add assignees to pull requests
+addAssignees: author
+
+# A list of assignees, overrides reviewers if set
+assignees:
+  - kentaro-m
+
+# A number of assignees to add to the pull request
+# Set to 0 to add all of the assignees.
+# Uses numberOfReviewers if unset.
+numberOfAssignees: 0
+
+# A list of keywords to be skipped the process that add reviewers if pull requests include it
+skipKeywords:
+  - wip

.github/workflows/pull-request.yml

@@ -0,0 +1,8 @@
+name: 'Auto Assign'
+on: pull_request
+
+jobs:
+  add-reviews:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: kentaro-m/auto-assign-action@v1.1.2