Loki-canary can't use both authentication and x-scope-orgid (tenant-id)

[kovaxur]

Describe the bug
Loki-canary is unable to use both authentication and tenant-id settings at the same time.

To Reproduce

1. Set username and password with the -user and -pass arguments
2. Set tenant-id with the -tenant-id argument

Expected behavior
Users should be able to set both headers at the same time.

Environment:

• Infrastructure: all
• Deployment tool: all

Screenshots, Promtail config, or terminal output

loki/pkg/canary/reader/reader.go

Lines 88 to 92 in 6d7422a

	if user != "" {
	h = http.Header{"Authorization": {"Basic " + base64.StdEncoding.EncodeToString([]byte(user+":"+pass))}}
	} else if tenantID != "" {
	h = http.Header{"X-Scope-OrgID": {tenantID}}
	}

[stale]

Hi! This issue has been automatically marked as stale because it has not had any
activity in the past 30 days.

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