chore: per template opt into cached terraform directories (#20609)

For experimental and dogfood purposes, this adds the ability to opt in a single template. 
Leaving the rest of the templates as is. 

For GA, this setting might be removed or changed.

coderd/database/modelqueries.go

@@ -127,6 +127,7 @@ func (q *sqlQuerier) GetAuthorizedTemplates(ctx context.Context, arg GetTemplate
 			&i.MaxPortSharingLevel,
 			&i.UseClassicParameterFlow,
 			&i.CorsBehavior,
+			&i.UseTerraformWorkspaceCache,
 			&i.CreatedByAvatarURL,
 			&i.CreatedByUsername,
 			&i.CreatedByName,