Fix YAML syntax error in workflow - convert multiline strings to escape sequences

Author: spbolton

.github/workflows/issue_comp_link-issue-to-pr.yml

@@ -186,9 +186,7 @@ jobs:
               fi
               
               updated_list=$(echo -e "$pr_list\n$new_pr_line" | sort -u)
-              new_body="## PRs linked to this issue
-
-$updated_list"
+              new_body="## PRs linked to this issue\n\n$updated_list"
               echo "pr_list=$new_body" >> "$GITHUB_OUTPUT"
             fi
           else
@@ -198,9 +196,7 @@ $updated_list"
               new_pr_line="$new_pr_line ✅"
             fi
             
-            new_body="## PRs linked to this issue
-
-$new_pr_line"
+            new_body="## PRs linked to this issue\n\n$new_pr_line"
             echo "pr_list=$new_body" >> "$GITHUB_OUTPUT"
           fi
 
@@ -237,10 +233,7 @@ $new_pr_line"
           if ! echo "$current_body" | grep -q "#$issue_number"; then
             # Add issue reference to PR body
             if [[ -n "$current_body" && "$current_body" != "null" ]]; then
-              new_body="$current_body
-
----
-*This PR addresses issue #$issue_number*"
+              new_body="$current_body\n\n---\n*This PR addresses issue #$issue_number*"
             else
               new_body="*This PR addresses issue #$issue_number*"
             fi