RUMM-2931 prevent reporting ANR when app is in background

[xgouchet]

What does this PR do?

Fixes #1067

This PR prevents reporting false positive ANRs when the application is in background.

Motivation

In some cases (#1067) the host application is in background and the SDK detekts multiple SDKs that are not actually perceived by the end user.

[codecov-commenter]

Codecov Report

Merging #1239 (9d3221b) into develop (a54ed7a) will increase coverage by 0.04%.
The diff coverage is 100.00%.

@@             Coverage Diff             @@
##           develop    #1239      +/-   ##
===========================================
+ Coverage    82.50%   82.53%   +0.04%     
===========================================
  Files          353      353              
  Lines        11832    11833       +1     
  Branches      2015     2016       +1     
===========================================
+ Hits          9761     9766       +5     
+ Misses        1461     1460       -1     
+ Partials       610      607       -3     

Impacted Files	Coverage Δ
...d/rum/internal/domain/scope/RumViewManagerScope.kt	98.17% <100.00%> (+0.02%)	⬆️
.../android/rum/internal/monitor/DatadogRumMonitor.kt	92.82% <0.00%> (-0.55%)	⬇️
...android/rum/internal/ndk/DatadogNdkCrashHandler.kt	87.19% <0.00%> (-0.49%)	⬇️
...in/com/datadog/android/log/internal/LogsFeature.kt	88.71% <0.00%> (ø)
...android/log/internal/logger/TelemetryLogHandler.kt	85.71% <0.00%> (ø)
...android/v2/core/internal/DatadogContextProvider.kt	83.82% <0.00%> (ø)
.../kotlin/com/datadog/android/v2/core/DatadogCore.kt	90.32% <0.00%> (+0.46%)	⬆️
...android/log/internal/domain/DatadogLogGenerator.kt	97.39% <0.00%> (+0.65%)	⬆️
...ndroid/telemetry/internal/TelemetryEventHandler.kt	73.77% <0.00%> (+1.64%)	⬆️
...d/v2/core/internal/storage/FileEventBatchWriter.kt	97.62% <0.00%> (+2.38%)	⬆️
... and 1 more

[emartynov]

Probably off topic - from names ANRDetectorRunnable.ANR_MESSAGE and ANRException I can not draw an understanding that it is a background ANR.

[emartynov]

Also, testedScope has applicationDisplayed as true, which sounds to me as if it is not in the background.