This PR replaces lambda with method reference whenever possible.

Comment From: philwebb

When we merge this I think we should convert it into distinct commits for the method refs vs other stuff.

Comment From: asashour

In this case, this PR would contain the method reference, and I would create a new one for the other changes, thanks.

Comment From: asashour

If I may say something, there is an error for some time that No space left on device. I am not sure if this is related to the PR content.

Comment From: philwebb

Thanks @asashour