Generalize mysql and mariadb version based on container name

This way we can split db_engine and db_version and simplify tests.
Also this is mandatory to use the matrix.db_engine_version as the
image name for our services containers.

tests/integration/targets/test_mysql_user/tasks/main.yml

@@ -243,7 +243,7 @@
     #
     # FIXME: mariadb sql syntax for create/update user is not compatible
     - include: test_user_plugin_auth.yml
-      when: install_type == 'mysql'
+      when: db_engine == 'mysql'
 
     # ============================================================
     # Assert create user with SELECT privileges, attempt to create database and update privileges to create database

tests/integration/targets/test_mysql_user/tasks/test_user_plugin_auth.yml

@@ -43,7 +43,7 @@
       assert:
         that:
           - "'{{ test_plugin_type }}' in show_create_user.stdout"
-      when: install_type == 'mysql' or (install_type == 'mariadb' and mariadb_version is version('10.3', '>='))
+      when: db_engine == 'mysql' or (db_engine == 'mariadb' and mariadb_version is version('10.3', '>='))
 
     - include: assert_user.yml user_name={{ test_user_name }} priv={{ test_default_priv_type }}
 
@@ -119,7 +119,7 @@
       assert:
         that:
           - "'{{ test_plugin_type }}' in show_create_user.stdout"
-      when: install_type == 'mysql' or (install_type == 'mariadb' and mariadb_version is version('10.3', '>='))
+      when: db_engine == 'mysql' or (db_engine == 'mariadb' and mariadb_version is version('10.3', '>='))
 
     - include: assert_user.yml user_name={{ test_user_name }} priv={{ test_default_priv_type }}
 
@@ -150,7 +150,7 @@
       assert:
         that:
           - result is not changed
-      when: install_type == 'mysql' or (install_type == 'mariadb' and mariadb_version is version('10.3', '>='))
+      when: db_engine == 'mysql' or (db_engine == 'mariadb' and mariadb_version is version('10.3', '>='))
 
     - include: assert_user.yml user_name={{ test_user_name }} priv={{ test_default_priv_type }}
 
@@ -211,7 +211,7 @@
       assert:
         that:
           - "'{{ test_plugin_type }}' in show_create_user.stdout"
-      when: install_type == 'mysql' or (install_type == 'mariadb' and mariadb_version is version('10.3', '>='))
+      when: db_engine == 'mysql' or (db_engine == 'mariadb' and mariadb_version is version('10.3', '>='))
 
     - include: assert_user.yml user_name={{ test_user_name }} priv={{ test_default_priv_type }}
 
@@ -301,7 +301,7 @@
       assert:
         that:
           - "'{{ test_plugin_type }}' in show_create_user.stdout"
-      when: install_type == 'mysql' or (install_type == 'mariadb' and mariadb_version is version('10.3', '>='))
+      when: db_engine == 'mysql' or (db_engine == 'mariadb' and mariadb_version is version('10.3', '>='))
 
     - include: assert_user.yml user_name={{ test_user_name }} priv={{ test_default_priv_type }}
 
@@ -387,7 +387,7 @@
         assert:
           that:
             - "'{{ test_plugin_type }}' in show_create_user.stdout"
-        when: install_type == 'mysql' or (install_type == 'mariadb' and mariadb_version is version('10.3', '>='))
+        when: db_engine == 'mysql' or (db_engine == 'mariadb' and mariadb_version is version('10.3', '>='))
 
       - include: assert_user.yml user_name={{ test_user_name }} priv={{ test_default_priv_type }}
 
@@ -412,7 +412,7 @@
         assert:
           that:
               - "'sha256_password' in show_create_user.stdout"
-        when: install_type == 'mysql' or (install_type == 'mariadb' and mariadb_version is version('10.3', '>='))
+        when: db_engine == 'mysql' or (db_engine == 'mariadb' and mariadb_version is version('10.3', '>='))
 
       - include: assert_user.yml user_name={{ test_user_name }} priv={{ test_default_priv_type }}