tests: baseparse: fix buffer leak in unit test
tests: baseparse: fix buffer leak in unit test

Fixes make check-valgrind

krichter722/gstreamer,centricular/gstreamer,jpxiong/gstreamer,centricular/gstreamer,StreamUtils/gstreamer,jpxiong/gstreamer,centricular/gstreamer,krichter722/gstreamer,krichter722/gstreamer,StreamUtils/gstreamer,krichter722/gstreamer,StreamUtils/gstreamer,jpxiong/gstreamer,StreamUtils/gstreamer,jpxiong/gstreamer,centricular/gstreamer,krichter722/gstreamer,centricular/gstreamer,StreamUtils/gstreamer,jpxiong/gstreamer