Merge pull request #812 from AdguardTeam/update-macos-requirement-to-12

Update installation.md - update macOS requirement to 12

Author: vyanovsky

docs/adguard-for-mac/installation.md

@@ -11,7 +11,7 @@ This article is about AdGuard for Mac, a multifunctional ad blocker that protect
 
 ## System requirements
 
-**Operating system version:** macOS 10.15 (64 bit) or higher
+**Operating system version:** macOS 12 or later
 
 **RAM:** at least 2 GB