[CI] Refactors Dockerfile to allow RUBY_SOURCE for docker image

Author: picandocodigo

.buildkite/Dockerfile

@@ -1,5 +1,6 @@
 ARG RUBY_VERSION=${RUBY_VERSION:-3.1}
-FROM ruby:$RUBY_VERSION
+ARG RUBY_SOURCE=${RUBY_SOURCE:-ruby}
+FROM $RUBY_SOURCE:$RUBY_VERSION
 
 # Default UID/GID to 1000
 # it can be overridden at build time

.buildkite/pipeline.yml

@@ -7,6 +7,7 @@ steps:
       TEST_SUITE: "{{ matrix.suite }}"
       STACK_VERSION: 8.10.0-SNAPSHOT
       TRANSPORT_VERSION: "{{ matrix.transport }}"
+      RUBY_SOURCE: "{{ matrix.ruby_source }}"
     matrix:
       setup:
         suite:
@@ -16,9 +17,10 @@ steps:
           - "3.2"
           - "3.1"
           - "3.0"
-          - "jruby-9.3"
         transport:
           - "8.2"
+        ruby_source:
+          - 'ruby'
       # Only run platinum once for the latest Ruby. You can use lots of combinations, check the
       # documentation on https://buildkite.com/docs/pipelines/build-matrix for more information.
       adjustments:
@@ -42,6 +44,10 @@ steps:
             suite: "free"
             ruby: "3.2"
             transport: "main"
+        - with:
+            suite: 'free'
+            ruby: '9.3'
+            ruby_source: 'jruby'
     command: ./.buildkite/run-tests.sh
     # I'm publishing test results to HTML and JUnit in this directory and this directive makes them
     # available in the Artifacts tab of a build in Buildkite.

.buildkite/run-client.sh

@@ -15,6 +15,7 @@ docker build \
        --tag elastic/elasticsearch-ruby \
        --build-arg RUBY_VERSION=$RUBY_VERSION \
        --build-arg TRANSPORT_VERSION=$TRANSPORT_VERSION \
+       --build-arg RUBY_SOURCE=$RUBY_SOURCE \
        .
 
 mkdir -p elasticsearch-api/tmp