fix: don't lint DerivedData and remove force unwrapping (#304)

Author: cbaker6

.swiftlint.yml

@@ -7,3 +7,4 @@ disabled_rules:
   - comment_spacing
 excluded: # paths to ignore during linting. Takes precedence over `included`.
   - Tests/ParseSwiftTests/ParseEncoderTests
+  - DerivedData

Sources/ParseSwift/Types/QueryWhere.swift

@@ -21,10 +21,10 @@ struct QueryWhere: Encodable, Equatable {
         var container = encoder.container(keyedBy: RawCodingKey.self)
         try constraints.forEach { (key, value) in
             try value.forEach { (constraint) in
-                if constraint.comparator != nil {
+                if let comparator = constraint.comparator {
                     var nestedContainer = container.nestedContainer(keyedBy: QueryConstraint.Comparator.self,
-                                                      forKey: .key(key))
-                    try constraint.encode(to: nestedContainer.superEncoder(forKey: constraint.comparator!))
+                                                                    forKey: .key(key))
+                    try constraint.encode(to: nestedContainer.superEncoder(forKey: comparator))
                 } else {
                     try container.encode(constraint, forKey: .key(key))
                 }