fix(jp): remove EOL-OS test definitions that fail in ca-central-1

These eight tests target operating systems whose package repositories
or AMIs have rotted out of ca-central-1 (where validation.yml runs)
since their EU originals were last validated:

- Debian 10 (Buster): EOL June 2024; archive.debian.org migration
  broke apt update flow on the AMI vintage available here.
- Ubuntu 18.04 (Bionic): EOL April 2023; `php-mysql` removed from
  the repos that the available AMI ships pointing at.
- Oracle Linux 8: standard AMIs no longer published in ca-central-1
  or ap-northeast-1 by Oracle's account (only paid Marketplace
  variants remain). Same failure on EU's nonregression daily.
- SUSE 15 SP3 BYOS: EOL'd; the matching AMI vintage is gone from
  both regions. Same failure on EU.

JP retains the modern equivalents already cloned from EU/US:
debian11/12/13-infra, suse154/155/156/157-infra, deb11-java tests,
ubuntu20-infra, awslinux2023 php-agent variants, etc. No coverage
lost — these eight were duplicates of obsolete OS variants.

Author: pranav-new-relic