Add support for remote-execution / caching of signapk actions

Test: "RBE_SIGNAPK=true RBE_SIGNAPK_EXEC_STRATEGY=remote ... use_rbe m" on crosshatch-userdebug and
signapk targets worked
Bug: b/156765091

Change-Id: I4b8c21320c2f38914ef39d3d8f036d885fab4e72
diff --git a/Android.bp b/Android.bp
index ec7d13a..73fad25 100644
--- a/Android.bp
+++ b/Android.bp
@@ -289,6 +289,7 @@
         "soong-dexpreopt",
         "soong-genrule",
         "soong-java-config",
+        "soong-remoteexec",
         "soong-tradefed",
     ],
     srcs: [