Remove changes related to persistence issue (#6191)

Revert changes related to persistence issue. These changes are still on
the `crashlytics-exception-handler` feature branch while we develop
there. `main` is now in a good state for the next release, including the
ODF and Session ID changes.

Author: mrober

firebase-crashlytics/firebase-crashlytics.gradle

@@ -98,7 +98,6 @@ dependencies {
     testImplementation(libs.mockito.core)
     testImplementation(libs.robolectric)
     testImplementation(libs.truth)
-    testImplementation(project(":integ-testing"))
 
     androidTestImplementation(libs.androidx.test.core)
     androidTestImplementation(libs.androidx.test.runner)