NPE when creating STUB with no headers section defined

[szymon-owczarzak]

aem-stubs/wiremock/src/main/java/com/cognifide/aem/stubs/wiremock/transformers/PebbleTransformer.java

Line 97 in d1935aa

HttpHeader header = definition.getHeaders().getHeader(ContentTypeHeader.KEY);

Wiremock does not require the headers section for the request/response sections. Please consider some reasonable defaults when header section is not present.

{
  "mappings": [
    {
      "request": {
        "method": "GET",
        "url": "/my-document-pdf"
      },
      "response": {
        "status": 200,
        "bodyFileName": "documents/my.pdf"
      }
    }
  ]
}

java.lang.NullPointerException: null
	at com.cognifide.aem.stubs.wiremock.transformers.PebbleTransformer.hasTextMimeType(PebbleTransformer.java:97) [com.cognifide.aem.stubs.wiremock:2.0.1]
	at com.cognifide.aem.stubs.wiremock.transformers.PebbleTransformer.lambda$transformBody$3(PebbleTransformer.java:88) [com.cognifide.aem.stubs.wiremock:2.0.1]
	at java.util.Optional.map(Optional.java:215)

[pun-ky]

@marcinkp hardening needed :)

[pun-ky]

IMO pebble templating is introducing many incompatibilities and I am quite sure that supporting it should be dropped