perf test for distance functions in a proper folder

dbms/tests/performance/string_search/ngram_distance.xml

+<test>
+    <name>Distance search performance search</name>
+
+    <tags>
+        <tag>search</tag>
+    </tags>
+
+    <preconditions>
+        <table_exists>hits_100m_single</table_exists>
+    </preconditions>
+
+    <type>loop</type>
+
+    <stop_conditions>
+        <all_of>
+            <iterations>5</iterations>
+            <min_time_not_changing_for_ms>10000</min_time_not_changing_for_ms>
+        </all_of>
+        <any_of>
+            <iterations>50</iterations>
+            <total_time_ms>60000</total_time_ms>
+        </any_of>
+    </stop_conditions>
+
+    <query>SELECT DISTINCT Title, ngramDistance(Title, 'what is love') AS distance FROM hits_100m_single ORDER BY distance ASC LIMIT 50</query>
+    <query>SELECT DISTINCT Title, ngramDistance(Title, 'baby dont hurt me') AS distance FROM hits_100m_single ORDER BY distance ASC LIMIT 50</query>
+    <query>SELECT DISTINCT Title, ngramDistance(Title, 'no more') AS distance FROM hits_100m_single ORDER BY distance ASC LIMIT 50</query>
+    <query>SELECT DISTINCT Title, ngramDistanceCaseInsensitive(Title, 'wHAt Is lovE') AS distance FROM hits_100m_single ORDER BY distance ASC LIMIT 50</query>
+    <query>SELECT DISTINCT Title, ngramDistanceCaseInsensitive(Title, 'BABY DonT hUrT me') AS distance FROM hits_100m_single ORDER BY distance ASC LIMIT 50</query>
+    <query>SELECT DISTINCT Title, ngramDistanceCaseInsensitive(Title, 'nO MOrE') AS distance FROM hits_100m_single ORDER BY distance ASC LIMIT 50</query>
+    <query>SELECT DISTINCT Title, ngramDistanceUTF8(Title, 'метрика') AS distance FROM {table} ORDER BY distance ASC LIMIT 50</query>
+    <query>SELECT DISTINCT URL, ngramDistanceUTF8(URL, 'как дела') AS distance FROM {table} ORDER BY distance ASC LIMIT 50</query>
+    <query>SELECT DISTINCT URL, ngramDistanceUTF8(URL, 'как дела') AS distance FROM {table} ORDER BY distance ASC LIMIT 50</query>
+
+    <query>SELECT DISTINCT Title, ngramDistanceUTF8CaseInsensitive(Title, 'Метрика') AS distance FROM {table} ORDER BY distance ASC LIMIT 50</query>
+    <query>SELECT DISTINCT URL, ngramDistanceUTF8CaseInsensitive(URL, 'как дЕлА') AS distance FROM {table} ORDER BY distance ASC LIMIT 50</query>
+    <query>SELECT DISTINCT URL, ngramDistanceUTF8CaseInsensitive(URL, 'Чем зАнимаешЬся') AS distance FROM {table} ORDER BY distance ASC LIMIT 50</query>
+
+    <main_metric>
+        <min_time/>
+    </main_metric>
+</test>