Add Learnpaths, Course Catalog, Course Header Images (#205)

* Add learnpath, catalog flag, header image path to courses

* Retreive course catalog endpoint

* fix: use correct variables in course update func

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Co-authored-by: Philip Prinz <Philip.Prinz@sva.de>

Author: jggoebel

v3/pkg/apis/hobbyfarm.io/v1/types.go

@@ -248,6 +248,10 @@ type CourseSpec struct {
 	PauseDuration     string              `json:"pause_duration"`
 	Pauseable         bool                `json:"pauseable"`
 	KeepVM            bool                `json:"keep_vm"`
+	IsLearnpath       bool                `json:"is_learnpath"`
+	IsLearnPathStrict bool                `json:"is_learnpath_strict"`
+	DisplayInCatalog  bool                `json:"in_catalog"`
+	HeaderImagePath   string              `json:"header_image_path"`
 }
 
 // +genclient