mariadb security best practice fixes

This commit ensures the below mariadb settings with reference to [0]:
 - 'local_infile' Is Disabled
 - 'have_symlink' Is Disabled
 - 'secure_file_priv' Is Not Empty
 - 'sql_mode' Contains 'STRICT_ALL_TABLES'

[0] https://dev.mysql.com/doc/mysql-security-excerpt/8.0/en/general-security-issues.html

Change-Id: I701b9bc2bdfb91d67aef91e88f953a09ac72d8be

mariadb/Chart.yaml

@@ -15,7 +15,7 @@ apiVersion: v1
 appVersion: v10.2.31
 description: OpenStack-Helm MariaDB
 name: mariadb
-version: 0.1.1
+version: 0.1.2
 home: https://mariadb.com/kb/en/
 icon: http://badges.mariadb.org/mariadb-badge-180x60.png
 sources:

mariadb/values.yaml

@@ -365,6 +365,16 @@ conf:
       max_connections=8192
       max-connect-errors=1000000
 
+      # General security settings
+      # Reference: https://dev.mysql.com/doc/mysql-security-excerpt/8.0/en/general-security-issues.html
+      # secure_file_priv is set to '/home' because it is read-only, which will
+      # disable this feature completely.
+      secure_file_priv=/home
+      local_infile=0
+      symbolic_links=0
+      sql_mode="STRICT_ALL_TABLES,STRICT_TRANS_TABLES,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"
+
+
       ## Generally, it is unwise to set the query cache to be larger than 64-128M
       ## as the costs associated with maintaining the cache outweigh the performance
       ## gains.