Add --timeout (-to) as an option to securityadmin.sh

[cwperks]

Description

Add --timeout (-to) as an option to securityadmin.sh

• Category (Enhancement, New feature, Bug fix, Test fix, Refactoring, Maintenance, Documentation)

Enhancement

Issues Resolved

Related to #5653

Check List

• New functionality includes testing
• New functionality has been documented
• New Roles/Permissions have a corresponding security dashboards plugin PR
• API changes companion pull request created
• Commits are signed per the DCO using --signoff

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.
For more information on following Developer Certificate of Origin and signing off your commits, please check here.

[codecov]

Codecov Report

❌ Patch coverage is 50.00000% with 8 lines in your changes missing coverage. Please review.
✅ Project coverage is 73.22%. Comparing base (2b0b41c) to head (b664c5d).

Files with missing lines	Patch %	Lines
...a/org/opensearch/security/tools/SecurityAdmin.java	50.00%	0 Missing and 8 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5787      +/-   ##
==========================================
- Coverage   73.26%   73.22%   -0.05%     
==========================================
  Files         434      434              
  Lines       26617    26621       +4     
  Branches     3963     3963              
==========================================
- Hits        19501    19493       -8     
- Misses       5219     5231      +12     
  Partials     1897     1897              

Files with missing lines	Coverage Δ
...a/org/opensearch/security/tools/SecurityAdmin.java	48.75% <50.00%> (+0.24%)	⬆️

... and 6 files with indirect coverage changes

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[DarshitChanpura]

should 30 s suffice?