bug setting CCPP_VERBOSITY=2

# Description

Setting `-DCCPP_VERBOSITY=n` for `n > 1` results in an invalid ccpp_capgen string

## Steps to Reproduce

2025-06-03-dev-6

Please provide detailed steps for reproducing the issue.

1. Invoke cmake from the top of the CCPP framework (so that include(cmake/ccpp_capgen.cmake) is executed).
2. Invoke cmake with the added argument -DCCPP_VERBOSITY=2
3. see the bug...
