DAOS-16876 vos: skip DTX record when load partial committed DTX

[Nasf-Fan]

It is used to handle existing partial committed DTX records that were
generated when ran as DAOS-2.6.3-rc{1,2} to avoid repeated DTX commit
after engine restarted.

To be safe, it is required for the user/admin to explicitly set server
side environment variable "DAOS_SKIP_OLD_PARTIAL_DTX" when restart the
engine that has ever run as DAOS-2.6.3-rc{1,2}. If the user has never
used such version, such as directly upgrading from 2.6.1 to 2.6.3-rc3
or newer, then please do NOT set this environment variable.

Before requesting gatekeeper:

• Two review approvals and any prior change requests have been resolved.
• Testing is complete and all tests passed or there is a reason documented in the PR why it should be force landed and forced-landing tag is set.
• Features: (or Test-tag*) commit pragma was used or there is a reason documented that there are no appropriate tags for this PR.
• Commit messages follows the guidelines outlined here.
• Any tests skipped by the ticket being addressed have been run and passed in the PR.

Gatekeeper:

• You are the appropriate gatekeeper to be landing the patch.
• The PR has 2 reviews by people familiar with the code, including appropriate owners.
• Githooks were used. If not, request that user install them and check copyright dates.
• Checkpatch issues are resolved. Pay particular attention to ones that will show up on future PRs.
• All builds have passed. Check non-required builds for any new compiler warnings.
• Sufficient testing is done. Check feature pragmas and test tags and that tests skipped for the ticket are run and now pass with the changes.
• If applicable, the PR has addressed any potential version compatibility issues.
• Check the target branch. If it is master branch, should the PR go to a feature branch? If it is a release branch, does it have merge approval in the JIRA ticket.
• Extra checks if forced landing is requested
  • Review comments are sufficiently resolved, particularly by prior reviewers that requested changes.
  • No new NLT or valgrind warnings. Check the classic view.
  • Quick-build or Quick-functional is not used.
• Fix the commit message upon landing. Check the standard here. Edit it to create a single commit. If necessary, ask submitter for a new summary.

[github-actions]

Ticket title is 'LRZ: m02r01s07dao engine coredumps with vos EMRG src/vos/ilog.c:411 ilog_open() Assertion'
Status is 'Awaiting Verification'
Labels: 'ALCF,LRZ,alcf_track,google-cloud-daos'
Job should run at elevated priority (1)
https://daosio.atlassian.net/browse/DAOS-16876

[daosbuild1]

Test stage NLT on EL 8.8 completed with status FAILURE. https://build.hpdd.intel.com/job/daos-stack/job/daos/job/PR-15883/2/display/redirect