cleanup metrics prepare.sh (#2676)

Author: vaind

metrics/prepare.sh

@@ -19,10 +19,6 @@ flutterCreate() {
 flutterCreate 'perf-test-app-plain'
 flutterCreate 'perf-test-app-with-sentry'
 
-# bump minSdkVersion to 21
-gradleFile="$targetDir/perf-test-app-with-sentry/android/app/build.gradle"
-sed "s/flutter.minSdkVersion/21/g" "$gradleFile" > "$gradleFile.new" && mv "$gradleFile.new" "$gradleFile"
-
 echo '::group::Patch perf-test-app-with-sentry'
 pubspec="$targetDir/perf-test-app-with-sentry/pubspec_overrides.yaml"
 echo "Adding dependencies to $pubspec"