Add race detector toggle for Tilt binaries

[mboersma]

/kind feature

Describe the solution you'd like

From Go's documentation for the data race detector:

...you may find more races by running a binary built with -race under a realistic workload.

Let's add a RACE_DETECTOR option for Tilt to build binaries with the -race flag. This option may help us to find previously undetected bugs that will undoubtedly arise in production environments otherwise.

Anything else you would like to add:

To work on this issue, you should have a local development environment with tilt set up as described in CAPZ's developer documentation.

Implementing this begins with the Tiltfile in the root of the project, where you can identify each place we go build a binary. Add an option that will be read from your local tilt-settings.json, and amend each go build to include the -race flag if the option is enabled. (Or something like that. 😄)

Please ask for help here on this GitHub issue or in the cluster-api-azure Slack channel.

See also #2646

[mboersma]

/help /good-first-issue /priority backlog

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[meghanajangi]

/assign

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[mboersma]

/unassign

[SD-13]

/assign