GitHub Action for CLA compliance (deephaven#1363)

* Added action for CLA compliance

* Add CLA to CONTRIBUTING.md

* Updated cla action

.github/workflows/cla.yml

@@ -0,0 +1,33 @@
+#
+# A GitHub Action to manage Contributor License Agreement (CLA) compliance.
+# This action uses CLA Assistant (https://github.com/marketplace/actions/cla-assistant-lite) to ensure that
+# all contributors have signed the Deephaven CLA before their PRs are merged.  
+# The CLA can be signed by commenting on the PR.
+#
+# The CLA and all signatures are maintained at:  https://github.com/deephaven/cla
+#
+
+name: "CLA Assistant"
+on:
+  issue_comment:
+    types: [created]
+  pull_request_target:
+    types: [opened,closed,synchronize]
+
+jobs:
+  CLAssistant:
+    runs-on: ubuntu-latest
+    steps:
+      - name: "CLA Assistant"
+        if: (github.event.comment.body == 'recheck' || github.event.comment.body == 'I have read the CLA Document and I hereby sign the CLA') || github.event_name == 'pull_request_target'
+        uses: cla-assistant/[email protected]
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          PERSONAL_ACCESS_TOKEN : ${{ secrets.CLA_PERSONAL_ACCESS_TOKEN }}
+        with:
+          path-to-document: 'https://github.com/deephaven/cla/blob/main/CLA.md'
+          remote-organization-name: deephaven
+          remote-repository-name:  cla
+          branch: 'main'
+          path-to-signatures: 'signatures/version1/cla.json'
+          #allowlist: user1,bot*

CONTRIBUTING.md

@@ -57,3 +57,6 @@ For more information, see:
 ## Styleguide
 The [styleguide](style/README.md) is applied globally to the entire project, except for generated code that gets checked in.
 To apply the styleguide, run `./gradlew spotlessApply`.
+
+## Deephaven Contributor License Agreement (CLA)
+The [Deephaven Contributor License Agreement (CLA)](https://github.com/deephaven/cla/blob/main/CLA.md) must be accepted before a pull request can be merged.  A bot monitors all pull requests.  Follow the instructions from the bot in the pull request comments to accept the CLA.  The Deephaven CLA and associated signatures are maintained at [https://github.com/deephaven/cla](https://github.com/deephaven/cla).