Add swiftlint rule to check for unsafe SFSymbol usage (#3700)

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Author: bgoncal

.swiftlint.yml

@@ -55,6 +55,7 @@ excluded:
   - Pods
   - vendor
   - "**/**/.build"
+  - "./.swiftlint.yml"
 
 custom_rules:
   prohibit_environment_assignment:
@@ -64,3 +65,9 @@ custom_rules:
     severity: error
     excluded:
       - "Tests"
+  sf_safe_symbol:
+    name: "Safe SFSymbol"
+    message: "Use `SFSafeSymbols` via `systemSymbol` parameters for type safety."
+    regex: >
+     (Image\\(systemName:)|(NSImage\\(symbolName:)|(Label[^,]+?,\\s*systemImage:)|(UIApplicationShortcutIcon\\(systemImageName:)
+    severity: warning