Update to .net7 and update from deprecated GH set-output command

[edumserrano]

Also added dependabot config.

[codecov]

Codecov Report

Merging #5 (7808db0) into main (161e879) will decrease coverage by 0.15%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main       #5      +/-   ##
==========================================
- Coverage   91.15%   91.00%   -0.15%     
==========================================
  Files          45       44       -1     
  Lines         486      478       -8     
  Branches       48       48              
==========================================
- Hits          443      435       -8     
  Misses         35       35              
  Partials        8        8              

Impacted Files	Coverage Δ
...iCommands/ParseLog/Outputs/JsonFileOutputFormat.cs	100.00% <ø> (ø)
...mands/ParseLog/Outputs/MarkdownFileOutputFormat.cs	100.00% <ø> (ø)
...g/Validators/NotNullOrWhitespaceOptionValidator.cs	100.00% <ø> (ø)
...mands/ParseLog/Validators/OutputOptionValidator.cs	83.33% <ø> (ø)
.../MarkdownLinkCheckLogParserCli/Files/OutputFile.cs	0.00% <ø> (ø)
...wnLinkCheckLogParserCli/GitHub/GitHubHttpClient.cs	57.14% <ø> (ø)
...kdownLinkCheckLogParserCli/GitHub/GitHubStepLog.cs	100.00% <ø> (ø)
...kCheckLogParserCli/GitHub/GitHubWorkflowRunLogs.cs	100.00% <ø> (ø)
...erCli/MarkdownLinkCheck/MarkdownLinkCheckOutput.cs	100.00% <ø> (ø)
...CheckLogParserCli/MarkdownLinkCheck/ParserState.cs	80.95% <ø> (ø)
... and 3 more

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