fix(misskey-js): content-typeはapplication/jsonでないもののみを記録するように (#14508)

packages/misskey-js/src/api.ts

@@ -56,6 +56,10 @@ export class APIClient {
 		return obj !== null && typeof obj === 'object' && !Array.isArray(obj);
 	}
 
+	private assertSpecialEpReqType(ep: keyof Endpoints): ep is keyof typeof endpointReqTypes {
+		return ep in endpointReqTypes;
+	}
+
 	public request<E extends keyof Endpoints, P extends Endpoints[E]['req']>(
 		endpoint: E,
 		params: P = {} as P,
@@ -63,9 +67,10 @@ export class APIClient {
 	): Promise<SwitchCaseResponseType<E, P>> {
 		return new Promise((resolve, reject) => {
 			let mediaType = 'application/json';
-			if (endpoint in endpointReqTypes) {
+			if (this.assertSpecialEpReqType(endpoint) && endpointReqTypes[endpoint] != null) {
 				mediaType = endpointReqTypes[endpoint];
 			}
+			
 			let payload: FormData | string = '{}';
 
 			if (mediaType === 'application/json') {
@@ -100,7 +105,7 @@ export class APIClient {
 				method: 'POST',
 				body: payload,
 				headers: {
-					'Content-Type': endpointReqTypes[endpoint],
+					'Content-Type': mediaType,
 				},
 				credentials: 'omit',
 				cache: 'no-cache',