fix: azure key vault variable (#4)

Author: LP-React

src/main/resources/application-prod.properties

@@ -1,7 +1,7 @@
 spring.application.name=webapi
 
 # ===== Azure Key Vault =====
-spring.cloud.azure.keyvault.secret.property-sources[0].endpoint={AZURE_KEY_VAULT_ENDPOINT}
+spring.cloud.azure.keyvault.secret.property-sources[0].endpoint=${AZURE_KEY_VAULT_ENDPOINT}
 
 # ===== PostgreSQL using secrets =====
 spring.datasource.url=${DB-URL-PROD}

src/main/resources/application-stage.properties

@@ -1,7 +1,7 @@
 spring.application.name=webapi
 
 # ===== Azure Key Vault =====
-spring.cloud.azure.keyvault.secret.property-sources[0].endpoint={AZURE_KEY_VAULT_ENDPOINT}
+spring.cloud.azure.keyvault.secret.property-sources[0].endpoint=${AZURE_KEY_VAULT_ENDPOINT}
 
 # ===== PostgreSQL using secrets =====
 spring.datasource.url=${DB-URL-STAGE}