[551] Exclude xtable-utilities from release guide

[vinishjail97]

Important Read

• Please ensure the GitHub issue is mentioned at the beginning of the PR

What is the purpose of the pull request

Excludes xtable-utilities from release scripts for generating source and validations.

Brief change log

(for example:)

• Excludes xtable-utilities from release scripts

Verify this pull request

(Please pick either of the following options)

This pull request is a trivial rework / code cleanup without any test coverage.

Verified the scripts through dry run and used them for releasing 0.2.0-incubating rc1 as well.