ingest/ledgerbackend: Skip removing storage dir when Captive-Core in front of requested ledger

[bartekn]

PR Checklist

PR Structure

• This PR has reasonably narrow scope (if not, break it down into smaller PRs).
• This PR avoids mixing refactoring changes with feature changes (split into two PRs
  otherwise).
• This PR's title starts with name of package that is most changed in the PR, ex.
  services/friendbot, or all or doc if the changes are broad or impact many
  packages.

Thoroughness

• This PR adds tests for the most critical parts of the new functionality or fixes.
• I've updated any docs (developer docs, .md
  files, etc... affected by this change). Take a look in the docs folder for a given service,
  like this one.

Release planning

• I've updated the relevant CHANGELOG (here for Horizon) if
  needed with deprecations, added features, breaking changes, and DB schema changes.
• I've decided if this PR requires a new major/minor version according to
  semver, or if it's mainly a patch change. The PR is targeted at the next
  release branch if it's not a patch change.

What

This commit improves stellarCoreRunner code to not remove storage dir if LCL of Captive-Core is greater than or equal requested from ledger.

Why

In e3d3abc we added a code that skips removing storage dir but it was not removed if and only if from argument matched the LCL of Stellar-Core. The problem is that in clusters with more than one ingesting instance it's possible that other ingesting node would ingest one or more ledgers while Captive-Core instance is being restarted. In such case we should not remove storage dir but just skip the ledgers we don't need.

Known limitations

[TODO or N/A]