Fix typo in error message when the same file is in both srcs and hdrs.

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MOS_MIGRATED_REVID=95852647

src/main/java/com/google/devtools/build/lib/rules/objc/CompilationSupport.java

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationSupport.java b/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationSupport.java
index 90c9bdd..98048e4 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationSupport.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationSupport.java
@@ -102,7 +102,7 @@
 
   @VisibleForTesting
   static final String FILE_IN_SRCS_AND_HDRS_ERROR_FORMAT =
-      "File '%s' is in both srcs in hdrs.";
+      "File '%s' is in both srcs and hdrs.";
 
   /**
    * Returns information about the given rule's compilation artifacts.