Update ruby-build to v20251217 (#480)

Author: erikaxel

lib/utils.sh

@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 
-RUBY_BUILD_VERSION="${ASDF_RUBY_BUILD_VERSION:-v20251203}"
+RUBY_BUILD_VERSION="${ASDF_RUBY_BUILD_VERSION:-v20251217}"
 RUBY_BUILD_TAG="$RUBY_BUILD_VERSION"
 
 echoerr() {