Section 13. An employee of a sheriff of an abolished county, or of Hampshire county after August 31, 1998 shall be an ''employee'' or ''public employee'' as defined in section 1 of chapter 150E and the sheriff of such county shall be an ''employer'' or ''public employer'' as defined in said section 1 of said chapter 150E. A collective bargaining agreement negotiated by each such sheriff shall be submitted to the governor in conformity with the provisions of subsection (c) of section 7 of said chapter 150E.