Update dependency com.google.code.gson:gson to v2.15.0

Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

lib/build.gradle

@@ -142,7 +142,7 @@ dependencies {
 
     implementation 'com.google.android.material:material:1.14.0'
 
-    api 'com.google.code.gson:gson:2.14.0'
+    api 'com.google.code.gson:gson:2.15.0'
 
     implementation 'io.reactivex.rxjava2:rxjava:2.2.21'
     implementation 'io.reactivex.rxjava3:rxjava:3.1.12'