Clean up SkyFunction interface method docs

Specifies function return values. Replaces old "builder" terminology. Removes bad advice.

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MOS_MIGRATED_REVID=90417023
diff --git a/src/main/java/com/google/devtools/build/skyframe/NodeEntry.java b/src/main/java/com/google/devtools/build/skyframe/NodeEntry.java
index 585b4e1..08ec804 100644
--- a/src/main/java/com/google/devtools/build/skyframe/NodeEntry.java
+++ b/src/main/java/com/google/devtools/build/skyframe/NodeEntry.java
@@ -238,7 +238,7 @@
   Set<SkyKey> markClean();
 
   /**
-   * Forces this node to be reevaluated, even if none of its dependencies are known to have
+   * Forces this node to be re-evaluated, even if none of its dependencies are known to have
    * changed.
    *
    * <p>Used when an external caller has reason to believe that re-evaluating may yield a new