Add approval monitor for unity_build_rule.cmake (#29701)

* Add approval monitor for unity_build_rule.cmake, test=develop

* fix words spell error, test=document_fix

tools/check_file_diff_approvals.sh

@@ -318,6 +318,22 @@ if [ "${HASUTFIXED}" != "" ]; then
   check_approval 1 52739577 46314656 12538138
 fi
 
+# NOTE(Avin0323): Files with the name "unity_build_rule.cmake" are rules used
+# by Unity Build to combine source files. Changes to these rules may cause
+# errors in the compilation. Specific personal are required to approve the
+# modification of these files.
+UNITYBUILD_RULE_CHANGED=$(git diff --name-only upstream/$BRANCH |
+                          grep "unity_build_rule.cmake" || true)
+if [ -n "${UNITYBUILD_RULE_CHANGED}" -a -n "${GIT_PR_ID}" ]; then
+    echo_line="You must have one RD (Avin0323(Recommend) or zhouwei25 or
+               wanghuancoder or luotao1) approval for modifying
+               unity_build_rule.cmake which the rules of Unity Build."
+    echo_line=$(echo ${echo_line})
+    # Avin0323(16167147) zhouwei25(52485244)
+    # wanghuancoder(26922892) luotao1(6836917)
+    check_approval 1 16167147 52485244 26922892 6836917
+fi
+
 if [ -n "${echo_list}" ];then
   echo "****************"
   echo -e "${echo_list[@]}"