Maintenance: check for Perl modules

[yadij]

... used by logic in ./scripts/ directory which
may be run during build, testing or release

[yadij]

diff of ./configure output

--- master.out	2026-01-10 17:55:36.716000309 +1300
+++ pr.out	2026-01-10 17:51:02.563210374 +1300
@@ -65,6 +65,17 @@
 checking pkg-config is at least version 0.9.0... yes
 checking for perl... /usr/bin/perl
 checking for pod2man... /usr/bin/pod2man
+checking for perl module strict... ok
+checking for perl module warnings... ok
+checking for perl module Carp... ok
+checking for perl module Fcntl... ok
+checking for perl module File::Basename... ok
+checking for perl module Getopt::Long... ok
+checking for perl module Getopt::Std... ok
+checking for perl module IO::File... ok
+checking for perl module IPC::Open2... ok
+checking for perl module Pod::Usage... ok
+checking for perl module Squid::ParseLog... no
 checking for ar... /usr/bin/ar
 checking for linuxdoc... /usr/bin/linuxdoc
 configure: strict error checking enabled: yes

[rousskov]

The proposed checks seem to be unused by any Squid code. Please adjust this PR description to clarify why they should be added.