gh-35563: Make doc preview message from github bot one liner
    
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### 📚 Description

For each PR, github bot emits a comment with documentation preview
message. Now it consists of two lines. This PR makes it one line, for
quick eye scan from left to right once instead of twice.

![Screen Shot 2023-04-25 at 2 41 40 PM](https://user-images.githubuserco
ntent.com/1456101/234184364-2e174edc-b895-470b-a675-cedbe1d263e8.png)

(I also tried to make the doc link open in a new tab, but it seems close
to impossible.)

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- [ ] I have linked a relevant issue or discussion.
- [ ] I have created tests covering the changes.
- [ ] I have updated the documentation accordingly.

### ⌛ Dependencies

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URL: #35563
Reported by: Kwankyu Lee
Reviewer(s): Matthias Köppe

Author: Release Manager

.github/workflows/doc-publish.yml

@@ -1,4 +1,4 @@
-# Triggers after the documentation build has finished, 
+# Triggers after the documentation build has finished,
 # taking the artifact and uploading it to netlify
 name: Publish documentation
 
@@ -47,7 +47,7 @@ jobs:
             });
             var fs = require('fs');
             fs.writeFileSync('${{github.workspace}}/docs.zip', Buffer.from(download.data));
-      
+
       - name: Extract docs
         run: unzip docs.zip -d docs && unzip docs/docs.zip -d docs/docs
 
@@ -72,9 +72,8 @@ jobs:
           header: preview-comment
           recreate: true
           message: |
-            [Documentation preview for this PR](${{ steps.deploy-netlify.outputs.NETLIFY_URL }}) is ready! :tada:
-            Built with commit: ${{ steps.source-run-info.outputs.sourceHeadSha }}
-      
+            [Documentation preview for this PR](${{ steps.deploy-netlify.outputs.NETLIFY_URL }}) (built with commit ${{ steps.source-run-info.outputs.sourceHeadSha }}) is ready! :tada:
+
       - name: Update deployment status PR check
         uses: myrotvorets/[email protected]
         if: ${{ always() }}