In bootstrap_java_library, use the javac from the exec/tool JDK, no…

…t the target JDK

The JDK is being used here as a tool that runs during the build (for javac), so it should be in the exec configuration.

See also unknown commit

PiperOrigin-RevId: 611588284
Change-Id: Iaaa9b6d92e03546ece3f1e833a4a532fada2e583

tools/build_rules/java_rules_skylark.bzl

@@ -216,6 +216,7 @@ java_library_attrs = {
     "_jdk": attr.label(
         default = Label("@bazel_tools//tools/jdk:current_java_runtime"),
         providers = [java_common.JavaRuntimeInfo],
+        cfg = "exec",
     ),
     "data": attr.label_list(allow_files = True),
     "resources": attr.label_list(allow_files = True),