configure.ac: modernise

3 jobs for fixes in 56 minutes and 2 seconds (queued for 7 seconds)
Status Name Job ID Coverage
  Test
passed job_clang_amd64 #5781
amd64

00:56:01

passed job_clang_cxx_amd64 #5782
amd64

00:10:56

passed job_gcc_amd64 #5780
amd64

00:47:34