ledger-tool: Minor cleanup on --ignore-ulimit-nofile-error flag

[steviez]

Problem

This argument is a flag and doesn't take a value; however, it had the .value_name() modifier set with "FORMAT". This could be confusing so remove .value_name() and add .takes_value(false).

Here is the only place where this argument is read; note that it checks for presence and not value:

solana/ledger-tool/src/ledger_utils.rs

Line 428 in b04765f

let enforce_ulimit_nofile = !matches.is_present("ignore_ulimit_nofile_error");

Before:

        --ignore-ulimit-nofile-error <FORMAT>
            Allow opening the blockstore to succeed even if the desired open file descriptor limit cannot be configured.
            Use with caution as some commands may run fine with a reduced file descriptor limit while others will not

After:

        --ignore-ulimit-nofile-error    Allow opening the blockstore to succeed even if the desired open file descriptor
                                        limit cannot be configured. Use with caution as some commands may run fine with
                                        a reduced file descriptor limit while others will not

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (b04765f) 81.6% compared to head (ba374b6) 81.6%.

Additional details and impacted files

@@            Coverage Diff            @@
##           master   #34944     +/-   ##
=========================================
- Coverage    81.6%    81.6%   -0.1%     
=========================================
  Files         828      828             
  Lines      224339   224339             
=========================================
- Hits       183274   183243     -31     
- Misses      41065    41096     +31     

[mergify]

Backports to the beta branch are to be avoided unless absolutely necessary for fixing bugs, security issues, and perf regressions. Changes intended for backport should be structured such that a minimum effective diff can be committed separately from any refactoring, plumbing, cleanup, etc that are not strictly necessary to achieve the goal. Any of the latter should go only into master and ride the normal stabilization schedule. Exceptions include CI/metrics changes, CLI improvements and documentation updates on a case by case basis.