Bump com.github.spullara.mustache.java:compiler

Bumps [com.github.spullara.mustache.java:compiler](https://github.com/spullara/mustache.java) from 0.9.10 to 0.9.12.
- [Commits](spullara/mustache.java@0.9.10...mustache.java-0.9.12)

---
updated-dependencies:
- dependency-name: com.github.spullara.mustache.java:compiler
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

modules/lang-mustache/build.gradle

@@ -38,7 +38,7 @@ opensearchplugin {
 }
 
 dependencies {
-  api "com.github.spullara.mustache.java:compiler:0.9.10"
+  api "com.github.spullara.mustache.java:compiler:0.9.12"
 }
 
 restResources {