fix(perf-simple-query): fix results table

When new column to perf simple query test is added it breaks the result
table.

Fix by getting available columns from current run and create table with
all of them. In case there's no result for that column in the past,
replace with `N/A`.

Fixes: #7496

sdcm/utils/microbenchmarking/perf_simple_query_reporter.py

@@ -54,6 +54,7 @@ def check_regression(self, test_id, mad_deviation_limit=0.02, regression_limit=0
             return False
 
         test_stats = self._get_perf_simple_query_result(doc)
+        columns = test_stats['stats'].keys()
         test_details = self._get_test_details(doc)
         if not (test_stats and test_details):
             self.log.debug("Could not find test statistics, regression check is skipped")
@@ -109,8 +110,11 @@ def make_table_line_for_render(data):
             table_line['test_version'] = data['results']['perf_simple_query_result']['versions'][
                 'scylla-server']
             stats = data['results']['perf_simple_query_result']['stats']
-            for key, value in stats.items():
+            for key in columns:
+                value = stats.get(key, 'N/A')
                 table_line[key] = value
+                if value == 'N/A':
+                    continue
                 if value > 0 and key != "mad tps":
                     diff = test_stats['stats'][key] / value
                     table_line["is_" + key + "_within_limits"] = False