Remove sandbox entitlement to allow tests to run on big sur. (flutter#92065)

Author: godofredoc

dev/integration_tests/flutter_gallery/macos/Runner/DebugProfile.entitlements

@@ -2,8 +2,6 @@
 <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
 <plist version="1.0">
 <dict>
-	<key>com.apple.security.app-sandbox</key>
-	<true/>
 	<key>com.apple.security.cs.allow-jit</key>
 	<true/>
 	<key>com.apple.security.network.server</key>