Update build image

Author: sarahchen6

.gitlab-ci.yml

@@ -29,7 +29,7 @@ variables:
   GRADLE_VERSION: "8.14.4" # must match gradle-wrapper.properties
   MAVEN_REPOSITORY_PROXY: "https://depot-read-api-java.us1.ddbuild.io/magicmirror/magicmirror/@current/"
   GRADLE_PLUGIN_PROXY: "https://depot-read-api-java.us1.ddbuild.io/magicmirror/magicmirror/@current/"
-  BUILDER_IMAGE_VERSION_PREFIX: "v26.02-" # use either an empty string (e.g. "") for latest images or a version followed by a hyphen (e.g. "v25.05-")
+  BUILDER_IMAGE_VERSION_PREFIX: "v26.03-" # use either an empty string (e.g. "") for latest images or a version followed by a hyphen (e.g. "v25.05-")
   REPO_NOTIFICATION_CHANNEL: "#apm-java-escalations"
   DEFAULT_TEST_JVMS: /^(8|11|17|21|25|tip)$/ # the latest "tip" version is 26
   PROFILE_TESTS: