Remove a print statement left over from debugging

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=170078105

core/src/main/java/com/google/googlejavaformat/OpsBuilder.java

diff --git a/core/src/main/java/com/google/googlejavaformat/OpsBuilder.java b/core/src/main/java/com/google/googlejavaformat/OpsBuilder.java
index 591327c..c7cea16 100644
--- a/core/src/main/java/com/google/googlejavaformat/OpsBuilder.java
+++ b/core/src/main/java/com/google/googlejavaformat/OpsBuilder.java
@@ -206,7 +206,6 @@
 
   /** Create a {@link FormatterDiagnostic} at the current position. */
   public FormatterDiagnostic diagnostic(String message) {
-    System.err.printf(">>>> %d: %s\n", inputPosition, message);
     return input.createDiagnostic(inputPosition, message);
   }