Update documentation for (new) contributors

[vanwinkelseppe]

Describe the proposal

Add a section in the documentation that contains more information on the available commands in the repository to help new contributors getting started.

• Linting golangci-lint run (after installing package taken from build pipeline)
• Tests. go test ./... (taken from build pipeline)

Also maybe we can update the pull request template to include:

• Linting
• Update docs