Added solution for day-1 - step-3

solution/day-1/step-3/hello-app-cm.yaml

+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: hello-app-cm
+data:
+  color: "#200"

solution/day-1/step-3/hello-app-deployment-secret.yaml

+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: hello-app-secret
+  labels:
+    app: hello-app
+spec:
+  replicas: 3
+  selector:
+    matchLabels:
+      app: hello-app
+  template:
+    metadata:
+      labels:
+        app: hello-app
+    spec:
+      imagePullSecrets:
+        - name: auth-master3-registry
+      containers:
+      - name: hello-app
+        image: registry.master3.takima.io/guide/kubernetes-resources/hello_world:latest
+        ports:
+        - containerPort: 3000
+        env:
+        - name: K8S_NODE_NAME
+          valueFrom:
+            fieldRef:
+              fieldPath: spec.nodeName
+        - name: K8S_POD_NAME
+          valueFrom:
+            fieldRef:
+              fieldPath: metadata.name
+        - name: K8S_POD_IP
+          valueFrom:
+            fieldRef:
+              fieldPath: status.podIP
+        - name: CUSTOM_COLOR # Vrai key de la variable d'env. Peut être différent de la valeur dans le config map
+          valueFrom:
+            secretKeyRef:
+              name: hello-app-secret  # Nom du configmap
+              key: color

solution/day-1/step-3/hello-app-deployment.yaml

+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: hello-app-deployment
+  labels:
+    app: hello-app
+spec:
+  replicas: 3
+  selector:
+    matchLabels:
+      app: hello-app
+  template:
+    metadata:
+      labels:
+        app: hello-app
+    spec:
+      imagePullSecrets:
+        - name: takima-school-registry
+      containers:
+      - name: hello-app
+        image: registry.gitlab.com/takima-school/images/simple-website:latest
+        ports:
+        - containerPort: 3000
+        env:
+        - name: K8S_NODE_NAME
+          valueFrom:
+            fieldRef:
+              fieldPath: spec.nodeName
+        - name: K8S_POD_NAME
+          valueFrom:
+            fieldRef:
+              fieldPath: metadata.name
+        - name: K8S_POD_IP
+          valueFrom:
+            fieldRef:
+              fieldPath: status.podIP
+        - name: CUSTOM_COLOR # Vrai key de la variable d'env. Peut être différent de la valeur dans le config map
+          valueFrom:
+            configMapKeyRef:
+              name: hello-app-cm  # Nom du configmap
+              key: color  

solution/day-1/step-3/hello-secret.yaml

+apiVersion: v1
+kind: Secret
+metadata:
+  name: hello-app-secret
+type: Opaque
+data:
+  color: IiMyMDAi