add caller name to _log_request_full log

Related-prod: PRODX-14905
Change-Id: Iee396e3078839fc05441afdc1f94d1d9549ce559
(cherry picked from commit 65c37a900b7b5be314650e10964f0a73d726a465)
(cherry picked from commit 4fd9afc8dcd213f9d86411222e4d777704bd23a5)
(cherry picked from commit e5a06a38e235fa1a22797a2defb399251882b28a)
diff --git a/tempest/lib/common/rest_client.py b/tempest/lib/common/rest_client.py
index 6cf5b73..a2f2931 100644
--- a/tempest/lib/common/rest_client.py
+++ b/tempest/lib/common/rest_client.py
@@ -456,13 +456,20 @@
         resp_log = resp.copy()
         if 'x-subject-token' in resp_log:
             resp_log['x-subject-token'] = '<omitted>'
-        log_fmt = """Request - Headers: %s
+        # NOTE(sdague): while we still have 6 callers to this function
+        # we're going to just provide work around on who is actually
+        # providing timings by gracefully adding no content if they don't.
+        # Once we're down to 1 caller, clean this up.
+        caller_name = test_utils.find_test_caller()
+
+        log_fmt = """Request (%s) - Headers: %s
         Body: %s
     Response - Headers: %s
         Body: %s"""
 
         self.LOG.debug(
             log_fmt,
+            caller_name,
             str(req_headers),
             self._safe_body(req_body),
             str(resp_log),