Fix issue with Jitsi compilation

Error was lots of `Duplicate class org.checkerframework.common.reflection.qual.MethodVal found in modules jetified-checker-3.1 (org.checkerframework:checker:3.1.1) and jetified-checker-qual-3.12.0 (org.checkerframework:checker-qual:3.12.0)
Cannot use latest 3.15.0 since it required min API 26.

Author: bmarty

vector/build.gradle

@@ -305,6 +305,11 @@ dependencies {
         exclude group: "org.jetbrains.kotlinx", module: "kotlinx-coroutines-debug"
     }
 
+    // Fix issue with Jitsi. Inspired from https://github.com/android/android-test/issues/861#issuecomment-872067868
+    // Error was lots of `Duplicate class org.checkerframework.common.reflection.qual.MethodVal found in modules jetified-checker-3.1 (org.checkerframework:checker:3.1.1) and jetified-checker-qual-3.12.0 (org.checkerframework:checker-qual:3.12.0)
+    //noinspection GradleDependency Cannot use latest 3.15.0 since it required min API 26.
+    implementation "org.checkerframework:checker:3.11.0"
+
     androidTestImplementation libs.androidx.testCore
     androidTestImplementation libs.androidx.testRunner
     androidTestImplementation libs.androidx.testRules