[R-pkg-team] Bug#1104406: dh-r: insufficiently strict versioning of dependencies on r-base-core when symbols are added

[Rebecca N. Palmer]

Package: dh-r
Version: 20241218

R 4.5 added at least one symbol (R_getVar) to the C API, but did not 
increment r-api.

Some R packages (that can be built against either R 4.4 or 4.5) link to 
this symbol when built against R 4.5.  Hence, if such a package is built 
against R 4.5, attempting to import it in R 4.4 will fail.  Such 
packages hence should Depend on r-base-core (>= 4.5.0~), but in current 
dh-r, they do not.

pkg-r-autopkgtest should catch this if it is run, but autopkgtests are 
only run for sourceful uploads, not binNMUs.  Hence, at least two such 
packages have reached testing: r-cran-svglite #1103369 and 
r-cran-timechange #1103118.