remove es.url and use the components (es.protocol, es.host, es.port) instead

[davidblasby]

I've noticed some inconsistencies in the es configuration.

By this I mean;

1. If I set es.host (vi the EnvVars), then it doesn't really really get used. It will be replaced with es.url - which will be localhost (defined earlier).
   • the EsRestClient partially used es.url and partially es.* vars.
   • RestClientBuilder builder = RestClient.builder(new HttpHost(serverHost, Integer.parseInt(serverPort), serverProtocol));
   • this is using the defined es.port, es.host, etc.. NOT THE es.url
2. the next line if (serverUrl.startsWith("https://")) -- this is using es.url INSTEAD of es.protocol

So, you must:

a. define all the es.* variables
b. have es.url consistent with the set variables.

This PR removes the es.url configuration and instead builds it directly from es.protocol, es.host, and es.port. Currently, es.url isn't really being used (EsRestClient uses the component not es.url). I've kept the serverUrl variable because its used in a few other places.

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[davidblasby]

@josegar74 -
Hi, jose, I reviewed your PR (es config with Environment vars).

I create some changes for it (this PR)

This is because es.url is problematic - its not consistent and has poor default values. Its also setting the same config values in two different ways. The code actually uses the individual components es.host - NOT the es.url. I've made that more consistent.

[davidblasby]

@josegar74 - please verify this.