Adds wiki guide for session searching

[zgoldman-r7]

Follow on to #18364

Addresses #18364 (comment) and #18364 (comment)

Verification steps:

• Look at the wiki and make sure the steps make sense
• Make sure new test passes
• Open up a session and do a sessions --search not_a_term:5 and make sure it prints the proper error message

[adfoster-r7]

Looks like the changes are failing:

build.rb:53:in `validate!': Unhandled paths Metasploit-Guide-Session-Search.md - add navigation entries to navigation.rb for these files (Build::ConfigValidationError)
	from build.rb:397:in `run'
	from build.rb:[5](https://github.com/rapid7/metasploit-framework/actions/runs/6580005862/job/17877067312?pr=18470#step:4:6)95:in `run'
	from build.rb:[6](https://github.com/rapid7/metasploit-framework/actions/runs/6580005862/job/17877067312?pr=18470#step:4:7)6[7](https://github.com/rapid7/metasploit-framework/actions/runs/6580005862/job/17877067312?pr=18470#step:4:8):in `<main>'
[!] Validation failed. Please verify navigation.rb is valid, as well as the markdown file

Because new files need to be added to navigation.rb

[adfoster-r7]

If we move this to be a higher level page:

docs/metasploit-framework.wiki/Managing-Sessions.md

[adfoster-r7]

Release Notes

Adds a new Wiki page for session management, detailing how to search for sessions and killing stale sessions