drop support for Perl < 5.14

IO::Socket::Inet requires us to have 5.14.

Author: simbabque

.github/workflows/dzil-build-and-test.yml

@@ -74,9 +74,6 @@ jobs:
       matrix:
         os: [ubuntu-latest]
         perl-version:
-          - "5.8"
-          - "5.10"
-          - "5.12"
           - "5.14"
           - "5.16"
           - "5.18"
@@ -116,9 +113,6 @@ jobs:
       matrix:
         os: [macos-latest]
         perl-version:
-          - "5.8"
-          - "5.10"
-          - "5.12"
           - "5.14"
           - "5.16"
           - "5.18"