Squashed 'apollo-ios-codegen/' changes from 54f10e351..7e754865b

7e754865b Improve error description formatting for validation failure (#846)

git-subtree-dir: apollo-ios-codegen
git-subtree-split: 7e754865ba8f7ebde21a99eb4ea222df8f5c2f54

Author: gh-action-runner

Sources/ApolloCodegenLib/ApolloCodegen+Errors.swift

@@ -23,7 +23,8 @@ extension ApolloCodegen {
       switch self {
       case let .graphQLSourceValidationFailure(lines):
         return """
-          An error occured during validation of the GraphQL schema or operations! Check \(lines)
+          An error occured during validation of the GraphQL schema or operations! Check:
+              \(lines.joined(separator: "\n    "))
           """
       case .testMocksInvalidSwiftPackageConfiguration:
         return """