Type parameters in object literal methods get extra unnecessary suffix in declaration files

Steps to reproduce

export const o = {
    foo<M extends string>(): void { },
    bar<M extends string>(): void { },
};

Each type parameter M has the name as they were written

export declare const o: {
    foo<M extends string>(): void;
    bar<M extends string>(): void;
};

Second type parameter is renamed to M_1

export declare const o: {
    foo<M extends string>(): void;
    bar<M_1 extends string>(): void;
};

Probably related to #3761 and co