[GNC] GNC 4.9 build with libicu library versions

[Mike Commissaris]

System:  Kernel: 5.15.0-3.1-liquorix-amd64 x86_64 bits: 64
               Distro: MX-21_ahs_x64 Wildflower October 10  2021
               base: Debian GNU/Linux 11 (bullseye)
 CPU:      Topology: 8-Core model: AMD Ryzen 7 5700U with Radeon Graphics
 Other:
 gcc (Debian 10.2.1-6) 10.2.1
  cmake version 3.18.4
  make 4.3
  libicu-dev 67.1
  libicu67

I have been building GNC for many versions and have always had to degrade
libicu libraries to version 63.1 to prevent the "make failed" citing
installed version 67.1 conflict. I got this new laptop and imagine my
surprise when I was able to build version 4.8 (and subsequently 4.9) with
libicu 67.1 installed.

But when I tried to build 4.9 on our office desktop I got the libicu
version failure. The desktop has:
kernel 5.10.0
gcc Debian 8.3.0-6
cmake 3.13.4
make 4.2.1
I had to downgrade and lock to libicu63.1 for successful 4.9 build.

All other GNC dependencies require a "version or higher" situation.
So  my question is why are libicu and libicu-dev libraries not the same as
far as accepting the higher version? Can I upgrade something to allow
version 67?



-- 
Mike