Propose additional TC members

[michellutz]

ii and JRC to propose additional TC members.

[cportele]

ii proposes the following TC members:

• Jon Herrmann: Architect and lead developer of the current version of ETF, in-depth knowledge and experience with developing tests with ETF v1 and ETF v2
• Clemens Portele: Member of the design team for the current version of ETF, lead designer of the workflow for the BaseX-based tests, contributor to GmlGeoX, documentation and other ETF repositories, in-depth knowledge and experience with developing tests with ETF v1 and ETF v2
• Johannes Echterhoff: Developer of the first version of GmlGeoX and active contributor to the library, in-depth knowledge and experience with developing BaseX-based tests with ETF v1 and ETF v2