http_jar repositories now load java_import from rules_java

Given the Starlarkification of the Java rules, the BUILD file
generated by http_jar() should no longer assume that java_import
is available as a Bazel builtin.

Author: dws

src/test/tools/bzlmod/MODULE.bazel.lock

@@ -191,6 +191,8 @@ def _http_file_impl(ctx):
     return _update_integrity_attr(ctx, _http_file_attrs, download_info)
 
 _HTTP_JAR_BUILD = """\
+load("@rules_java//java:java_import.bzl", "java_import")
+
 package(default_visibility = ["//visibility:public"])
 
 java_import(