fix: align test app directory with plugin directory

[sebastienrouif]

There is currently a mismatch between the plugin and the test application.
The plugin uses the test application package val deviceScreenshotDir = androidTest.applicationId.map { "/storage/emulated/0/Download/screenshots/$it" } whereas the application was using the application's package val context = InstrumentationRegistry.getInstrumentation().targetContext

this broke recording and other tasks, such as clearing and pulling screenshots

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1 out of 2 committers have signed the CLA.

✅ sebastienrouif
❌ sebastiennavico
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