test(mysql): configure to read committed (#305)

related to camunda/camunda-bpm-platform#4516

Author: tasso94

test/docker-compose.yml

@@ -13,7 +13,7 @@ services:
         platform: linux/${PLATFORM}
         environment:
             - DB_DRIVER=com.mysql.cj.jdbc.Driver
-            - DB_URL=jdbc:mysql://mysql:3306/process-engine?sendFractionalSeconds=false
+            - DB_URL=jdbc:mysql://mysql:3306/process-engine?sendFractionalSeconds=false&sessionVariables=transaction_isolation='READ-COMMITTED'
             - DB_USERNAME=camunda
             - DB_PASSWORD=camunda
             - WAIT_FOR=mysql:3306
@@ -63,7 +63,7 @@ services:
         platform: linux/${PLATFORM}
         environment:
             - DB_DRIVER=com.mysql.cj.jdbc.Driver
-            - DB_URL=jdbc:mysql://mysql:3306/process-engine?sendFractionalSeconds=false
+            - DB_URL=jdbc:mysql://mysql:3306/process-engine?sendFractionalSeconds=false&sessionVariables=transaction_isolation='READ-COMMITTED'
             - DB_USERNAME=camunda
             - DB_PASSWORD_FILE=/run/secrets/camunda_db_password
             - WAIT_FOR=mysql:3306