3.0 regression: FreeType leaks
Lot of text styls are leaked, e.g.:
Direct leak of 720 byte(s) in 9 object(s) allocated from:
[#0](https://code.videolan.org/videolan/vlc/-/issues/0) 0x7f47f750a4e1 in __interceptor_calloc (/usr/lib/x86_64-linux-gnu/libasan.so.2+0x944e1)
[#1](https://code.videolan.org/videolan/vlc/-/issues/1) 0x7f47f4d37f12 in text_style_Duplicate ../../src/misc/text_style.c:140
[#2](https://code.videolan.org/videolan/vlc/-/issues/2) 0x7f47d1810c14 in SegmentsToTextAndStyles ../../modules/text_renderer/freetype.c:921
[#3](https://code.videolan.org/videolan/vlc/-/issues/3) 0x7f47d18111dc in Render ../../modules/text_renderer/freetype.c:962
[#4](https://code.videolan.org/videolan/vlc/-/issues/4) 0x7f47f4c6fede in SpuRenderText ../../src/video_output/vout_subpictures.c:279
[#5](https://code.videolan.org/videolan/vlc/-/issues/5) 0x7f47f4c74b3b in SpuRenderRegion ../../src/video_output/vout_subpictures.c:678
[#6](https://code.videolan.org/videolan/vlc/-/issues/6) 0x7f47f4c7a714 in SpuRenderSubpictures ../../src/video_output/vout_subpictures.c:1057
[#7](https://code.videolan.org/videolan/vlc/-/issues/7) 0x7f47f4c7de65 in spu_Render ../../src/video_output/vout_subpictures.c:1477
[#8](https://code.videolan.org/videolan/vlc/-/issues/8) 0x7f47f4c5dc8b in ThreadDisplayRenderPicture ../../src/video_output/video_output.c:906
[#9](https://code.videolan.org/videolan/vlc/-/issues/9) 0x7f47f4c5f841 in ThreadDisplayPicture ../../src/video_output/video_output.c:1083
[#10](https://code.videolan.org/videolan/vlc/-/issues/10) 0x7f47f4c658dc in Thread ../../src/video_output/video_output.c:1578
[#11](https://code.videolan.org/videolan/vlc/-/issues/11) 0x7f47f629a0a3 in start_thread (/lib/x86_64-linux-gnu/libpthread.so.0+0x80a3)
No comparable problem in VLC 2.2.