Templates. Update versions

Revert to 6.9 as 7.1.1 doesn't properly work with com.android.tools.build:gradle:4.0.1
com.android.tools.build:gradle:7.0.0 doesn't supported by IDEA yet

templates/multiplatform-template/gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-7.1.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.9-all.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists