backport #17068: qt: Always generate `bitcoinstrings.cpp` on `make translate`
backport #17068: qt: Always generate `bitcoinstrings.cpp` on `make translate`

`bitcoinstrings.cpp` is to be generated at release time. Hence,
it should not depend on whether the source files are younger as the
releaser may proceed from a fresh checkout.

UdjinM6/dash,dashpay/dash,thelazier/dash,UdjinM6/dash,dashpay/dash,thelazier/dash,thelazier/dash,dashpay/dash,UdjinM6/dash,thelazier/dash,UdjinM6/dash,dashpay/dash,dashpay/dash,thelazier/dash,UdjinM6/dash