chore: add template toggle to disable module caching (#21931)

There exists use cases to disable the new module caching behavior of
workspace builds. This was the legacy behavior.

codersdk/templates.go

@@ -64,6 +64,10 @@ type Template struct {
 	CORSBehavior         CORSBehavior                 `json:"cors_behavior"`
 
 	UseClassicParameterFlow bool `json:"use_classic_parameter_flow"`
+
+	// DisableModuleCache disables the use of cached Terraform modules during
+	// provisioning.
+	DisableModuleCache bool `json:"disable_module_cache"`
 }
 
 // WeekdaysToBitmap converts a list of weekdays to a bitmap in accordance with
@@ -263,6 +267,9 @@ type UpdateTemplateMeta struct {
 	// made the default.
 	// An "opt-out" is present in case the new feature breaks some existing templates.
 	UseClassicParameterFlow *bool `json:"use_classic_parameter_flow,omitempty"`
+	// DisableModuleCache disables the using of cached Terraform modules during
+	// provisioning. It is recommended not to disable this.
+	DisableModuleCache *bool `json:"disable_module_cache,omitempty"`
 }
 
 type TemplateExample struct {