Fix load schema pointer type

Author: eddeee888

.changeset/famous-spiders-call.md

@@ -0,0 +1,5 @@
+---
+'@graphql-codegen/cli': patch
+---
+
+Fix schema pointers type to allow an array of pointers

packages/graphql-codegen-cli/src/config.ts

@@ -422,7 +422,7 @@ export class CodegenContext {
     return this._pluginContext;
   }
 
-  async loadSchema(pointer: Types.Schema): Promise<GraphQLSchema> {
+  async loadSchema(pointer: Types.Schema | Types.Schema[]): Promise<GraphQLSchema> {
     const config = this.getConfig(defaultSchemaLoadOptions);
     if (this._graphqlConfig) {
       // TODO: SchemaWithLoader won't work here

packages/graphql-codegen-cli/src/load.ts

@@ -28,7 +28,7 @@ export const defaultDocumentsLoadOptions = {
 };
 
 export async function loadSchema(
-  schemaPointers: UnnormalizedTypeDefPointer,
+  schemaPointers: UnnormalizedTypeDefPointer | UnnormalizedTypeDefPointer[],
   config: Types.Config
 ): Promise<GraphQLSchema> {
   try {