chore(iast): add re.match with an index to the leak testing script (#10742)

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Signed-off-by: Juanjo Alvarez <[email protected]>

Author: juanjux

scripts/iast/mod_leak_functions.py

@@ -74,10 +74,11 @@ def test_doit():
     re_match = re.compile(r"(\w+)", re.IGNORECASE)
     re_match_result = re_match.match(string21)  # 1 propagation: 'HIROOT
 
-    string22 = re_match_result.group(0)  # 1 propagation: '_HIROOT
-    # string22 = re_match_result.groups()[0]
+    string22_1 = re_match_result[0]  # 1 propagation: '_HIROOT
+    string22_2 = re_match_result.groups()[0]  # 1 propagation: '_HIROOT
+    string22 = string22_1 + string22_2  # 1 propagation: _HIROOT_HIROOT
     tmp_str = "DDDD"
-    string23 = tmp_str + string22  # 1 propagation: 'DDDD_HIROOT
+    string23 = tmp_str + string22  # 1 propagation: 'DDDD_HIROOT_HIROOT
 
     re_match = re.compile(r"(\w+)(_+)(\w+)", re.IGNORECASE)
     re_match_result = re_match.search(string23)