Bump mariadb-java-client from 2.7.1 to 2.7.3

Bumps [mariadb-java-client](https://github.com/mariadb-corporation/mariadb-connector-j) from 2.7.1 to 2.7.3.
- [Release notes](https://github.com/mariadb-corporation/mariadb-connector-j/releases)
- [Changelog](https://github.com/mariadb-corporation/mariadb-connector-j/blob/master/CHANGELOG.md)
- [Commits](https://github.com/mariadb-corporation/mariadb-connector-j/commits)

Signed-off-by: dependabot-preview[bot] <[email protected]>

Author: dependabot-preview[bot]

core/build.gradle

@@ -14,7 +14,7 @@ dependencies {
 
     api 'com.zaxxer:HikariCP:4.0.3'
     //    compile group: 'mysql', name: 'mysql-connector-java', version: '8.0.17'
-    implementation 'org.mariadb.jdbc:mariadb-java-client:2.7.1'
+    implementation 'org.mariadb.jdbc:mariadb-java-client:2.7.3'
 
 //    api "co.aikar:idb-core:1.0.0-SNAPSHOT"
     api 'com.github.Fernthedev:db:292c0bb'