Change "rule" -> "target" in existing_rule() docs

RELNOTES: None
PiperOrigin-RevId: 218559308
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/SkylarkNativeModuleApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/SkylarkNativeModuleApi.java
index 3e73359..0e4149e 100644
--- a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/SkylarkNativeModuleApi.java
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/SkylarkNativeModuleApi.java
@@ -89,10 +89,13 @@
   @SkylarkCallable(
     name = "existing_rule",
     doc =
-        "Returns a dictionary representing the attributes of a previously defined rule, "
-            + "or None if the rule does not exist.",
+        "Returns a dictionary representing the attributes of a previously defined target, or "
+            + "<code>None</code> if the target does not exist."
+            + ""
+            + "<p><i>Note: If possible, avoid using this function. It makes BUILD files brittle "
+            + "and order-dependent.",
     parameters = {
-      @Param(name = "name", type = String.class, doc = "The name of the rule.")
+      @Param(name = "name", type = String.class, doc = "The name of the target.")
     },
     useAst = true,
     useEnvironment = true
@@ -103,9 +106,12 @@
   @SkylarkCallable(
     name = "existing_rules",
     doc =
-        "Returns a dict containing all the rules instantiated so far. "
-            + "The map key is the name of the rule. The map value is equivalent to the "
-            + "existing_rule output for that rule.",
+        "Returns a dictionary containing all the targets instantiated so far. The map key is the "
+            + "name of the target. The map value is equivalent to the <code>existing_rule</code> "
+            + "output for that target."
+            + ""
+            + "<p><i>Note: If possible, avoid using this function. It makes BUILD files brittle "
+            + "and order-dependent.",
     useAst = true,
     useEnvironment = true
   )