Drop two comments that restate or misdescribe the code

The javadoc on throwIfLikeConditionUnderIcuCollation repeated the rationale
that CoreError.COLLATION_ICU_LIKE_CONDITION_NOT_SUPPORTED already states.

The SnapshotKeyTest comment described a boundary sentinel that
Snapshot.Key.buildIdentity does not have. The test name states the intent.

Author: Torch3333

core/src/main/java/com/scalar/db/transaction/consensuscommit/ConsensusCommitOperationChecker.java

@@ -53,11 +53,6 @@ public ConsensusCommitOperationChecker(
     this.collation = collation;
   }
 
-  /**
-   * Rejects a LIKE or NOT_LIKE condition under the ICU collation. This layer re-evaluates a
-   * selection's conditions itself and its pattern matching stays byte-exact at any collation, so on
-   * a backend whose own collation governs LIKE the two would disagree.
-   */
   private void throwIfLikeConditionUnderIcuCollation(Selection selection) {
     if (collation != Collation.ICU) {
       return;

core/src/test/java/com/scalar/db/transaction/consensuscommit/SnapshotKeyTest.java

@@ -353,8 +353,7 @@ private Get prepareGetWithCompositePartitionKey(String value1, String value2) {
   @Test
   public void
       equals_CompositePartitionKeyVsSplitPartitionAndClusteringKeyUnderIcuPrimary_ShouldStayDistinct() {
-    // Arrange: both shapes flatten to the TEXT components ['a', 'b'], so only the boundary
-    // sentinel and the clustering-key presence marker keep their identities apart.
+    // Arrange
     Snapshot.Key compositeKey =
         new Snapshot.Key(
             prepareGetWithCompositePartitionKey("a", "b"),