fixed typo

Signed-off-by: Alexander Piskun <[email protected]>

Author: bigcat88

.github/SECURITY.md

@@ -8,7 +8,8 @@ Fix time is approximately from 1 to 3 days.
 
 ## Reporting a Vulnerability
 
-Transparency and Security is very important. All builds are made using GitHub Actions only and for macOS Arm64 using CirrusCI.
+Transparency and Security are vital.
+All builds are made using GitHub Actions only and for macOS Arm64 using CirrusCI.
 No part of the releases is published from any local source, the release process is fully automated from start to finish.
 
 Please report security vulnerabilities to [email protected] with `Pillow-Heif` in the subject line.