Update mariadb

Changes:

- https://github.com/docker-library/mariadb/commit/195b4c1: Update to 1:10.1.39+maria-1~bionic

library/mariadb

@@ -19,9 +19,9 @@ Architectures: amd64, arm64v8, ppc64le
 GitCommit: fa087985605ca508ac661a52164db8c292c9f779
 Directory: 10.2
 
-Tags: 10.1.38-bionic, 10.1-bionic, 10.1.38, 10.1
+Tags: 10.1.39-bionic, 10.1-bionic, 10.1.39, 10.1
 Architectures: amd64, arm64v8, ppc64le
-GitCommit: 93f1e9c9082364522c77b94e98299d7d398089f8
+GitCommit: 195b4c1448069ce769b0e0e5648b2623f6b83b66
 Directory: 10.1
 
 Tags: 10.0.38-xenial, 10.0-xenial, 10.0.38, 10.0