dev: improve migration suggestion for gomodguardv2

[ldez]

When there is no explicit configuration, the current suggestion is:

linters:
  enable:
    - gomodguard_v2
  settings:
    gomodguard_v2:
      allowed: []
      blocked: []
      local-replace-directives: false 

with this PR, the suggestion is:

linters:
  enable:
    - gomodguard_v2

Same thing when the other fields are not explicitly set.

[bombsimon]

Should this be replacement? It's only for the d.Replacement settings key and not linter["settings"].

Suggested change

	settings := mgr(data)
	if settings != nil {
	linters["settings"] = map[string]any{d.Replacement: settings}
	}
	replacement := mgr(data)
	if settings != nil {
	linters["settings"] = map[string]any{d.Replacement: replacement}
	}