Update migrating-from-static.md

[mikempx]

Running existing static to flow conversion with "grafana-agent" insinuated that I still needed the old agent. By default, the executable is named, "grafana-agent-flow" in the documentation and doesn't mention a need to rename the executable.

PR Description

Which issue(s) this PR fixes

Notes to the Reviewer

PR Checklist

• CHANGELOG.md updated
• Documentation added
• Tests updated
• Config converters updated

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✅ clayton-cornell
❌ mikempx
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[clayton-cornell]

@erikbaranowski Can you take a look at this? Is this the right solution or is there something else going on here that we need to account for?

[clayton-cornell]

@mikempx Can you sign the CLA whenyou get a chance :-)

[erikbaranowski]

@clayton-cornell the converter will work with either binary. It requires the env var only for the grafana-agent binary since Flow mode is not the default. I'm comfortable with documenting it in the converter guides however makes sense for clarity and consistency.

[clayton-cornell]

@erikbaranowski maybe we document it both ways?

If you're using Grafana Agent static mode: AGENT_MODE=flow grafana-agent convert --source-format=static --bypass-errors --output=OUTPUT_CONFIG_PATH INPUT_CONFIG_PATH

If you're using Grafana Agent flow mode: grafana-agent-flow convert --source-format=static --bypass-errors --output=OUTPUT_CONFIG_PATH INPUT_CONFIG_PATH

[erikbaranowski]

I'm good with documenting both since we have done so in places like here: https://grafana.com/docs/agent/latest/flow/reference/cli/run/.

Let's update all 3 migration guides if we are making this change for consistency.

[clayton-cornell]

@mikempx I'm going to close this PR. Your request resulted in a larger change to the docs than was implemented here and it was easier/faster and cleaner to open a new PR to take care of the change.

The new PR is: #5544