Configure gitlab pipeline to use Go 1.18.1 (#20186)

Signed-off-by: Mustafa Kara <mustafa.kara@mattermost.com>
Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

.gitlab-ci.yml

@@ -12,7 +12,7 @@ include:
 
 variables:
   BUILD: "yes"
-  IMAGE_BUILD_SERVER: $CI_REGISTRY/mattermost/ci/images/mattermost-build-server:20210810_golang-1.16.7
+  IMAGE_BUILD_SERVER: $CI_REGISTRY/mattermost/ci/images/mattermost-build-server:20220415_golang-1.18.1
   IMAGE_BUILD_DOCKER: $CI_REGISTRY/mattermost/ci/images/mattermost-build-docker:19.03.14-1
   IMAGE_DIND: $CI_REGISTRY/mattermost/ci/images/docker-dind:19.03.14-1