relax import for_each validation

Import blocks with for_each were intended to require resource blocks
with a matching expansion. This validation however did not take place in
prior releases, and configurations with this mismatch currently exist in
production.

That simple validation also does not take into account a single resource
instance inside of an expanded module, which is a valid use case and
harder to check for at the point of validation. That will still fail
correctly during plan if the targets are not available.

We can skip this validation for now, and work on generating static
validation errors later on if possible, taking into account the expanded
module case.

internal/terraform/context_apply_deferred_test.go

@@ -2915,7 +2915,7 @@ import {
 				wantDeferred: make(map[string]ExpectedDeferred),
 				wantDiagnostic: func(diags tfdiags.Diagnostics) bool {
 					for _, diag := range diags {
-						if diag.Description().Summary == "Use of import for_each in an invalid context" {
+						if diag.Description().Summary == "Resource has no configuration" {
 							return true
 						}
 					}

internal/terraform/node_resource_validate.go

@@ -572,20 +572,7 @@ func (n *NodeValidatableResource) validateImportTargets(ctx EvalContext) tfdiags
 			return diags
 		}
 
-		// Resource config might be nil here since we are also validating config generation.
-		expanded := n.Config != nil && (n.Config.ForEach != nil || n.Config.Count != nil)
-
 		if imp.Config.ForEach != nil {
-			if !expanded {
-				diags = diags.Append(&hcl.Diagnostic{
-					Severity: hcl.DiagError,
-					Summary:  "Use of import for_each in an invalid context",
-					Detail:   "Use of for_each in import requires a resource using count or for_each.",
-					// FIXME: minor issue, but this points to the for_each expression rather than for_each itself.
-					Subject: imp.Config.ForEach.Range().Ptr(),
-				})
-			}
-
 			forEachData, _, forEachDiags := newForEachEvaluator(imp.Config.ForEach, ctx, true).ImportValues()
 			diags = diags.Append(forEachDiags)
 			if forEachDiags.HasErrors() {