build: bump gradle wrapper version to 8.7

bdk-android/gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,7 @@
-#Thu Mar 28 12:04:56 EDT 2024
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.4-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.7-all.zip
+networkTimeout=10000
+validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists