CH-142 Update docs regarding dockerfile build args

docs/applications/README.md

@@ -117,6 +117,8 @@ The most important configuration entries are the following:
   - `use_services` (`{name, src, dst}[]`): create reverse proxy endpoints in the ingress for the listed applications on [subdomain].[Values.domain]/proxy/[name]. Useful to avoid CORS requests from frontend clients
   - `readinessProbe`: defines a a url to use as a readiness probe
   - `livenessProbe`: defines a a url to use as a liveness probe
+  - `dockerfile`: configuration for the dockerfile, currently only implemented in Skaffold
+    - `buildArgs`: a map of build arguments to provide to the dockerfile when building with Skaffold
 
 # Example code
 - [Sample application](../../applications/samples) is a sample web application providing working examples of deployment configuration, backend and frontend code.

docs/build-deploy/ci-cd/README.md

@@ -15,6 +15,10 @@ All you need to to is:
 - Run `skaffold build`
 - Run `skaffold run`
 
+### Dockerfile configuration with Skaffold
+
+When defining an applications values you can provide details on dockerfile configuration such as build arguments. This feature is intended to support useful development use cases (e.g. conditionally running unit tests via build arguments) and should be used with caution as it can lead to different images in different deployment environments.
+
 ## CI/CD with Codefresh
 
 [Codefresh](https://codefresh.io/) is a nice platform for CI/CD see details in the [dedicated document](./codefresh.md).

libraries/models/api/openapi.yaml

@@ -715,7 +715,14 @@ components:
             properties:
                 buildArgs:
                     $ref: '#/components/schemas/SimpleMap'
-                    description: Map of build arguments to provide to the dockerfile at build time
+                    description: >-
+                        Map of build arguments to provide to the dockerfile at build time.
+
+
+                        The use of this feature is to aid in development (e.g. not running tests on every
+                        local build) and not for setting environment variables in different environments;
+                        caution should be taken when using this feature as it can lead to inconsistent
+                        behaviour across environments. 
         HarnessMainConfig:
             description: ''
             required: