fix(cli): handle version mismatch re MatchedProvisioners response (#15682)

* Modifies `MatchedProvisioners` response of `codersdk.TemplateVersion`
to be a pointer
* CLI now checks for absence of `*MatchedProvisioners` before showing
warning regarding provisioners
* Extracts logic for warning about provisioners to a function
* Improves test coverage for CLI template push with
`coder_workspace_tags`.

codersdk/provisionerdaemons.go

@@ -53,6 +53,7 @@ type ProvisionerDaemon struct {
 
 // MatchedProvisioners represents the number of provisioner daemons
 // available to take a job at a specific point in time.
+// Introduced in Coder version 2.18.0.
 type MatchedProvisioners struct {
 	// Count is the number of provisioner daemons that matched the given
 	// tags. If the count is 0, it means no provisioner daemons matched the

codersdk/templateversions.go

@@ -32,7 +32,7 @@ type TemplateVersion struct {
 	Archived       bool           `json:"archived"`
 
 	Warnings            []TemplateVersionWarning `json:"warnings,omitempty" enums:"DEPRECATED_PARAMETERS"`
-	MatchedProvisioners MatchedProvisioners      `json:"matched_provisioners,omitempty"`
+	MatchedProvisioners *MatchedProvisioners     `json:"matched_provisioners,omitempty"`
 }
 
 type TemplateVersionExternalAuth struct {