CI: Flush the CPAN cache if /usr/bin/perl has been updated since #1182

Job	Run time
Empty APLOGNO() test	24s
Default	2m 9s
All-static modules	1m 49s
Prefork MPM, all-modules (except cgid)	2m 17s
Worker MPM, all-modules	2m 53s
Shared MPMs, all-modules	2m 21s
Event MPM, all-modules, mod_cgid only	2m 18s
Event MPM, all-modules, no CMSG_DATA	2m 17s
Default, all-modules + install	2m 34s
Default, all-modules, random test order	2m 34s
GCC 10 maintainer-mode w/-Werror, install + VPATH	42s
All-modules, APR 1.7.4, APR-util 1.6.3	3m 6s
APR 1.8.x, APR-util 1.7.x	6m 9s
Pool-debug	6m 17s
Shared MPMs (event), pool-debug, SSL/TLS variants	9m 39s
Shared MPMs (worker), pool-debug, SSL/TLS variants	9m 37s
Shared MPMs (prefork), pool-debug, SSL/TLS variants	9m 28s
litmus WebDAV tests	2m 0s
litmus WebDAV tests, APR trunk, LMDB	2m 29s
Regenerate ap_expr	2m 24s
APR 1.7.4, APR-util 1.6.3, LDAP	3m 37s
APR 1.7.x, APR-util 1.7.x, LDAP	5m 43s
APR trunk thread debugging	2m 48s
UBSan	3m 17s
ASan	7m 1s
ASan, pool-debug	7m 40s
HTTP/2 test suite	7m 37s
Configured w/reduced exports	2m 7s
OpenSSL 3.1	27s
OpenSSL 3.2 -Werror	27s
OpenSSL 3.2 no-engine	26s
OpenSSL 3.3 no-engine -Werror	48s
	1h 55m 25s

Provide feedback