Merge branch 'ruby-2.6.6' into 'master'

Bump Ruby to 2.6.6

Closes gitlab-org/charts/gitlab#2056 and gitlab-org/charts/gitlab#2059

See merge request gitlab-org/build/CNG!445

gitlab-ruby/Dockerfile

@@ -2,7 +2,7 @@ FROM debian:stretch-slim
 
 ARG BUILD_DIR=/tmp/build
 ARG RUBY_MAJOR_VERSION=2.6
-ARG RUBY_MINOR_VERSION=2.6.5
+ARG RUBY_MINOR_VERSION=2.6.6
 ARG RUBYGEMS_VERSION=2.7.10
 ARG BUNDLER_VERSION=1.17.3
 

gitlab-ruby/Dockerfile.build.ubi8

@@ -3,7 +3,7 @@ ARG BUILD_IMAGE=
 FROM ${BUILD_IMAGE}
 
 ARG RUBY_MAJOR_VERSION=2.6
-ARG RUBY_MINOR_VERSION=2.6.5
+ARG RUBY_MINOR_VERSION=2.6.6
 ARG RUBYGEMS_VERSION=2.7.10
 ARG BUNDLER_VERSION=1.17.3
 ARG RBREADLINE_VERSION=0.5.5