Update batch spec search result looping example (#870)

The original snippet has some issues:
The loop will not handle spaces correctly and may misinterpret the path.
The entire string is treated as one entity due to the quotes, leading to
incorrect processing.

Updated the loop handling in the script to correctly process file paths
by switching from space-delimited to newline-delimited entries. This
ensures the handling of paths with spaces or special characters. Added
IFS=$'\n' for proper splitting and quoting of paths in the loop for
safety.

![Screenshot 2024-12-19 at 3 10
35 PM](https://github.com/user-attachments/assets/4f10c4bb-cba2-4659-862f-4980c2c0b7c1)
Spaces in file names
![Screenshot 2024-12-19 at 3 09
23 PM](https://github.com/user-attachments/assets/771935b7-6d84-4bf7-bc0e-f7fe1b01959c)

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Author: gabtorre

docs/batch-changes/batch-spec-cheat-sheet.mdx

@@ -14,9 +14,11 @@ on:
 
 steps:
   - run: |
-      for file in "${{ join repository.search_result_paths " " }}";
+      IFS=$'\n'
+      files="${{ join repository.search_result_paths "\n" }}"
+      for file in $files;
       do
-        sed -i 's/OLD-VALUE/NEW-VALUE/g;' ${file}
+        sed -i 's/OLD-VALUE/NEW-VALUE/g;' "${file}"
       done
     container: alpine:3
 ```