Fix NPE in SystemCapabilityManager

[JulianKast]

Fixes #1729

This PR is [ready] for review.

Risk

This PR makes [no] API changes.

Testing Plan

• I have verified that I have not introduced new warnings in this PR (or explain why below)
• I have run the unit tests with this PR
• I have tested this PR against Core and verified behavior (if applicable, if not applicable, explain why below).
• I have tested Android, Java SE, and Java EE

Core Tests

Core version / branch / commit hash / module tested against: Sync 2.0, Sync 3.0, Core 7.1.1
HMI name / version / branch / commit hash / module tested against: Sync 2.0, Sync 3.0, generic_hmi

Summary

Added check to avoid NPE in SystemCapabilityManager, Fixes issue with text not appearing on Sync 2.0

Changelog

Bug Fixes

• Added check to avoid NPE in SystemCapabilityManager

CLA

• I have signed the CLA

[codecov]

Codecov Report

Merging #1734 (93407eb) into develop (6834f99) will decrease coverage by 0.00%.
The diff coverage is 100.00%.

❗ Current head 93407eb differs from pull request most recent head 1e85ab2. Consider uploading reports for the commit 1e85ab2 to get more accurate results

@@              Coverage Diff              @@
##             develop    #1734      +/-   ##
=============================================
- Coverage      54.37%   54.37%   -0.01%     
- Complexity      5494     5497       +3     
=============================================
  Files            562      562              
  Lines          25449    25450       +1     
  Branches        3309     3310       +1     
=============================================
  Hits           13838    13838              
- Misses         10357    10358       +1     
  Partials        1254     1254              

Impacted Files	Coverage Δ
...anagers/lifecycle/BaseSystemCapabilityManager.java	67.67% <100.00%> (+0.44%)	⬆️
...rtdevicelink/streaming/video/SdlRemoteDisplay.java	50.00% <0.00%> (-2.44%)	⬇️