Bump to rules_scala 7.12.3

Bazel 6.5.0 and 7.4.1 build. 8.0.0rc6 and 8.0.0rc7 both fail as
described previously.

Author: mbland

scala/private/macros/scala_repositories.bzl

@@ -157,9 +157,9 @@ def load_rules_dependencies():
         http_archive(
             name = "rules_java",
             urls = [
-                "https://github.com/bazelbuild/rules_java/releases/download/7.12.2/rules_java-7.12.2.tar.gz",
+                "https://github.com/bazelbuild/rules_java/releases/download/7.12.3/rules_java-7.12.3.tar.gz",
             ],
-            sha256 = "a9690bc00c538246880d5c83c233e4deb83fe885f54c21bb445eb8116a180b83",
+            sha256 = "c0ee60f8757f140c157fc2c7af703d819514de6e025ebf70386d38bdd85fce83",
         )
 
     if not native.existing_rule("rules_proto"):