Run benchmark at tag to track performances (#6035)

.drone.yml

@@ -195,6 +195,42 @@ pipeline:
     when:
       event: [ push, tag, pull_request ]
 
+  bench-sqlite:
+    image: golang:1.11
+    pull: true
+    group: bench
+    commands:
+      - make bench-sqlite
+    when:
+      event: [ tag ]
+
+  bench-mysql:
+    image: golang:1.11
+    pull: true
+    group: bench
+    commands:
+      - make bench-mysql
+    when:
+      event: [ tag ]
+
+  bench-mssql:
+    image: golang:1.11
+    pull: true
+    group: bench
+    commands:
+      - make bench-mssql
+    when:
+      event: [ tag ]
+
+  bench-pgsql:
+    image: golang:1.11
+    pull: true
+    group: bench
+    commands:
+      - make bench-pgsql
+    when:
+      event: [ tag ]
+
   generate-coverage:
     image: golang:1.11
     pull: true