No longer require building kvssink to build samples

[stefankiesz]

What was changed? BUILD_GSTREAMER_PLUGIN is no longer required to be ON for non-kvssink samples to be built. Added new flag BUILD_SAMPLES which defaults to ON to control the building of samples.

NOTE: GStreamer installation is still required for all samples.

Why was it changed? To allow for the building of non-kvssink samples without the need for building kvssink.

How was it changed? By removing the sample targets from the BUILD_GSTREAMER_PLUGIN conditional and adding the to a BUILD_SAMPLES conditional.

What testing was done for the changes? The CI will pass, and testing will be done locally on Mac.

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 16.51%. Comparing base (ca558f7) to head (0013fd9).

:exclamation: Current head 0013fd9 differs from pull request most recent head 72a9ede. Consider uploading reports for the commit 72a9ede to get more accurate results

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #1159      +/-   ##
===========================================
+ Coverage    16.48%   16.51%   +0.03%     
===========================================
  Files           50       50              
  Lines         7019     7022       +3     
===========================================
+ Hits          1157     1160       +3     
  Misses        5862     5862              

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[stefankiesz]

Remember to update ReadMe to reflect this