update changelog for 1.20.0 release (#174)

diff --git a/CHANGES.md b/CHANGES.md
index a436d50..c015e4e 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -16,6 +16,11 @@
 # limitations under the License.
 #
 -->
+# 1.20.0
+- Support array result include sequence action (#170)
+- Upgrade to Gradle 6 (#172)
+- Drop support for go 1.16 (#169)
+
 # 1.19.0
 - Add support for go 1.18 and go 1.17
 - Drop support for go 1.13 and go 1.15