Fix toBinary example in MIGRATING.md

[HermanBilous]

toBinary is declared as

export declare function toBinary<Desc extends DescMessage>(schema: Desc, message: MessageShape<Desc>, options?: Partial<BinaryWriteOptions>): Uint8Array;

[timostamm]

Thanks for the PR, Herman.

I think we already fixed this typo in #1338.

Do we have a link somewhere that points to MIGRATING.md on the v2.0.0 tag? Please let us know if we do, and we'll fix it to point to the main branch instead, where the typo is fixed.

[HermanBilous]

Hi! I swear I was trying to fix a different line. I updated the pr with correct fix.

[timostamm]

Oh, thanks for the fix Herman!