Add to API file and bump version

Author: mrwillis21

encoders/firebase-encoders-json/api.txt

@@ -72,6 +72,7 @@ package com.google.firebase.encoders.json {
     ctor public JsonDataEncoderBuilder();
     method @NonNull public com.google.firebase.encoders.DataEncoder build();
     method @NonNull public com.google.firebase.encoders.json.JsonDataEncoderBuilder configureWith(@NonNull com.google.firebase.encoders.config.Configurator);
+    method @NonNull public com.google.firebase.encoders.json.JsonDataEncoderBuilder ignoreNullValues(boolean);
     method @NonNull public <T> com.google.firebase.encoders.json.JsonDataEncoderBuilder registerEncoder(@NonNull Class<T>, @NonNull com.google.firebase.encoders.ObjectEncoder<? super T>);
     method @NonNull public <T> com.google.firebase.encoders.json.JsonDataEncoderBuilder registerEncoder(@NonNull Class<T>, @NonNull com.google.firebase.encoders.ValueEncoder<? super T>);
     method @NonNull public com.google.firebase.encoders.json.JsonDataEncoderBuilder registerFallbackEncoder(@NonNull com.google.firebase.encoders.ObjectEncoder<java.lang.Object>);

encoders/firebase-encoders-json/gradle.properties

@@ -12,4 +12,4 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-version=16.0.1
+version=16.1.0