[KYUUBI #971] [LICENSE] Add DISCLAIMER to binary release

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Closes #971 from pan3793/disclaimer.

Closes #971

c0fe3821 [Cheng Pan] [LICENSE] Add DISCLAIMER to binary release

Authored-by: Cheng Pan <chengpan@apache.org>
Signed-off-by: Cheng Pan <chengpan@apache.org>
(cherry picked from commit 2f82f33e9d)
Signed-off-by: Cheng Pan <chengpan@apache.org>

build/dist

@@ -216,6 +216,7 @@ if [[ "$SPARK_PROVIDED" != "true" ]]; then
 fi
 
 # Copy license files
+cp "$KYUUBI_HOME/DISCLAIMER" "$DISTDIR/DISCLAIMER"
 cp "$KYUUBI_HOME/LICENSE-binary" "$DISTDIR/LICENSE"
 cp -r "$KYUUBI_HOME/licenses-binary" "$DISTDIR/licenses"
 $KYUUBI_HOME/build/release/collect-licenses.sh "$DISTDIR" "$DISTDIR"