Merge pull request #593 from jacobweinstock/osie-baseurl-bugfix

Fix how we check for OSIE.BaseURL:

## Description

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The object that gets returned from Kubernetes seems to always come back non-nil. So we need to also check if the string is empty.

## Why is this needed

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Fixes: #

## How Has This Been Tested?
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## How are existing users impacted? What migration steps/scripts do we need?

<!--- Fixes a bug, unblocks installation, removes a component of the stack etc -->
<!--- Requires a DB migration script, etc. -->


## Checklist:

I have:

- [ ] updated the documentation and/or roadmap (if required)
- [ ] added unit or e2e tests
- [ ] provided instructions on how to upgrade

internal/ipxe/script/ipxe.go

@@ -287,7 +287,7 @@ func (h *Handler) defaultScript(span trace.Span, hw data) (string, error) {
 		Retries:               h.IPXEScriptRetries,
 		RetryDelay:            h.IPXEScriptRetryDelay,
 	}
-	if hw.OSIE.BaseURL != nil {
+	if hw.OSIE.BaseURL != nil && hw.OSIE.BaseURL.String() != "" {
 		auto.DownloadURL = hw.OSIE.BaseURL.String()
 	}
 	if hw.OSIE.Kernel != "" {