Bump Gradle Wrapper to 6.7 (#30200)

Summary:
Bump Gradle Wrapper to 6.7, to keep tooling on edge. Here are the highlights of this release:
- File system watching is ready for production use
- Declare the version of Java your build requires
- Java 15 support

## Changelog

[Android] [Changed] - Bump Gradle Wrapper to 6.7

Pull Request resolved: #30200

Test Plan: RNTester builds and runs as expected. Also my apps.

Reviewed By: cpojer

Differential Revision: D24560233

Pulled By: fkgozali

fbshipit-source-id: 0d94b4527b2ee5b28b22478128c25761929fbdc7

gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.6-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.7-all.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

packages/react-native-codegen/android/gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.6-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.7-all.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

template/android/gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.6-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.7-all.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists