Update gradle wrapper

gradle/wrapper/gradle-wrapper.properties

-# Quasseldroid - Quassel client for Android
-#
-# Copyright (c) 2019 Janne Mareike Koschinski
-# Copyright (c) 2019 The Quassel Project
-#
-# This program is free software: you can redistribute it and/or modify it
-# under the terms of the GNU General Public License version 3 as published
-# by the Free Software Foundation.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License along
-# with this program. If not, see <http://www.gnu.org/licenses/>.
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.0.2-bin.zip
+distributionSha256Szm=0e46229820205440b48a5501122002842b82886e76af35f0f3a069243dca4b3c
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https://services.gradle.org/distributions/gradle-7.0.1-all.zip