Fix godoc formatting for Lists and OptionalTypes functions

[chaewonkong]

This PR fixes the godoc formatting for the Lists and OptionalTypes functions by removing unnecessary blank lines. These blank lines caused godoc to misinterpret the documentation structure, leading to incomplete rendering. Now, the documentation is correctly parsed and consistently formatted.

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[TristonianJones]

/gcbrun

[TristonianJones]

Thanks @chaewonkong!