Add miekg/dns instrumentation

[MrAlias]

This new module instruments the github.com/miekg/dns package.

• Comply with OpenTelemetry semantic conventions (there are currently no requirements)
• Package documentation
• Exported objects are documented
• Tests and linting are passing
• Includes dependabot config
• Library added to README.md
• CHANGELOG.md updated

[codecov-commenter]

Codecov Report

Merging #155 (39bf8e7) into main (cad2c87) will increase coverage by 1.63%.
The diff coverage is 92.52%.

@@            Coverage Diff             @@
##             main     #155      +/-   ##
==========================================
+ Coverage   69.19%   70.83%   +1.63%     
==========================================
  Files          29       33       +4     
  Lines        1422     1529     +107     
==========================================
+ Hits          984     1083      +99     
- Misses        401      407       +6     
- Partials       37       39       +2     

Flag	Coverage Δ
Linux	70.17% <92.52%> (+1.68%)	⬆️
Windows	65.94% <92.52%> (+2.49%)	⬆️
macOS	67.49% <92.52%> (+1.88%)	⬆️

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Impacted Files	Coverage Δ
...trumentation/github.com/miekg/dns/splunkdns/dns.go	69.23% <69.23%> (ø)
...mentation/github.com/miekg/dns/splunkdns/config.go	93.75% <93.75%> (ø)
...mentation/github.com/miekg/dns/splunkdns/client.go	100.00% <100.00%> (ø)
...entation/github.com/miekg/dns/splunkdns/handler.go	100.00% <100.00%> (ø)

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[pellared]

Entry in CHANGELOG.md is missing 😉

I have reviewed it quickly. It would be better if @TomRoSystems would give it another pass.

[pellared]

nit

Suggested change

	assert.NoError(t, <-errCh, "failed to start server")
	assert.NoError(t, <-errCh, "server.ActivateAndServe returned an error")

as there may be multiple reasons why it returns an error

moreover, I hope this error message would make it easier to find where the error comes from