chore: Support 'untake' for unassigning github issues (apache#18637)

## Which issue does this PR close?

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enhancements and this helps us generate change logs for our releases.
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- Closes apache#18574

## Rationale for this change

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Why are you proposing this change? If this is already explained clearly
in the issue then this section is not needed.
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your changes and offer better suggestions for fixes.
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See the issue; tldr we couldn't do it before, and it sometimes leads me
to start work on something without 'take'-ing it

## What changes are included in this PR?

<!--
There is no need to duplicate the description in the issue here but it
is sometimes worth providing a summary of the individual changes in this
PR.
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Adds support for 'untake' command to allow contributors to manually
unassign themselves. Previously they would have to ask a committer to
unassign them

## Are these changes tested?

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2. Serve as another way to document the expected behavior of the code

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I tested this exact file in a personal repo I created. See
[here](petern48/test-repo#1)

## Are there any user-facing changes?

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updated before approving the PR.
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No, only for contributors
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---------

Co-authored-by: Martin Grigorov <martin-g@users.noreply.github.com>

Author: petern48

.github/workflows/take.yml

@@ -15,7 +15,7 @@
 # specific language governing permissions and limitations
 # under the License.
 
-name: Assign the issue via a `take` comment
+name: Assign/unassign the issue via `take` or `untake` comment
 on:
   issue_comment:
     types: created
@@ -26,16 +26,30 @@ permissions:
 jobs:
   issue_assign:
     runs-on: ubuntu-latest
-    if: (!github.event.issue.pull_request) && github.event.comment.body == 'take'
+    if: (!github.event.issue.pull_request) && (github.event.comment.body == 'take' || github.event.comment.body == 'untake')
     concurrency:
       group: ${{ github.actor }}-issue-assign
     steps:
-      - run: |
-          CODE=$(curl -H "Authorization: token ${{ secrets.GITHUB_TOKEN }}" -LI https://api.github.com/repos/${{ github.repository }}/issues/${{ github.event.issue.number }}/assignees/${{ github.event.comment.user.login }} -o /dev/null -w '%{http_code}\n' -s)
-          if [ "$CODE" -eq "204" ]
+      - name: Take or untake issue
+        env:
+          COMMENT_BODY: ${{ github.event.comment.body }}
+          ISSUE_NUMBER: ${{ github.event.issue.number }}
+          USER_LOGIN: ${{ github.event.comment.user.login }}
+          REPO: ${{ github.repository }}
+          TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          if [ "$COMMENT_BODY" == "take" ]
           then
-            echo "Assigning issue ${{ github.event.issue.number }} to ${{ github.event.comment.user.login }}"
-            curl -H "Authorization: token ${{ secrets.GITHUB_TOKEN }}" -d '{"assignees": ["${{ github.event.comment.user.login }}"]}' https://api.github.com/repos/${{ github.repository }}/issues/${{ github.event.issue.number }}/assignees
-          else
-            echo "Cannot assign issue ${{ github.event.issue.number }} to ${{ github.event.comment.user.login }}"
+            CODE=$(curl -H "Authorization: token $TOKEN" -LI https://api.github.com/repos/$REPO/issues/$ISSUE_NUMBER/assignees/$USER_LOGIN -o /dev/null -w '%{http_code}\n' -s)
+            if [ "$CODE" -eq "204" ]
+            then
+              echo "Assigning issue $ISSUE_NUMBER to $USER_LOGIN"
+              curl -X POST -H "Authorization: token $TOKEN" -H "Content-Type: application/json" -d "{\"assignees\": [\"$USER_LOGIN\"]}" https://api.github.com/repos/$REPO/issues/$ISSUE_NUMBER/assignees
+            else
+              echo "Cannot assign issue $ISSUE_NUMBER to $USER_LOGIN"
+            fi
+          elif [ "$COMMENT_BODY" == "untake" ]
+          then
+            echo "Unassigning issue $ISSUE_NUMBER from $USER_LOGIN"
+            curl -X DELETE -H "Authorization: token $TOKEN" -H "Content-Type: application/json" -d "{\"assignees\": [\"$USER_LOGIN\"]}" https://api.github.com/repos/$REPO/issues/$ISSUE_NUMBER/assignees
           fi

docs/source/contributor-guide/index.md

@@ -59,9 +59,8 @@ If you want to work on an issue which is not already assigned to someone else
 and there are no comment indicating that someone is already working on that
 issue then you can assign the issue to yourself by submitting a single word
 comment `take`. This will assign the issue to yourself. However, if you are
-unable to make progress you should unassign the issue by using the `unassign me`
-link at the top of the issue page (and ask for help if are stuck) so that
-someone else can get involved in the work.
+unable to make progress you should unassign the issue by commenting a single
+word `untake`.
 
 # Developer's guide