skparagraph: fix another leak

Change-Id: I2394dfb10994ce055d87f881ea3bd3c88ab634d6
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/258881
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Hal Canary <halcanary@google.com>
1 file changed