Interprets $TOKEN to it's .env file value for port parsing

[syko9000]

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Description

When a port uses a template variable, "$PORT:8080", specified in the .env file. Currently the port link on the container view shows "$PORT" and is not clickable. This fix parses out the $TOKEN's and replaces them with the value in the .env file before creating the URL link. Also, if not present the default value specified inline, example ${PORT:-8080}, "8080" would replace the token if PORT is not specified. Handles .env file vars in double or single quotes and unescapes any in the string if needed.

The interpreter will handle any values, not just ports, but only used for ports at this point.

It does not handle nested tokens, example ${PORT:-${DEFAULT_PORT}}

Fixes #237

Type of change

• Bug fix (non-breaking change which fixes an issue)

Checklist

• My code follows the style guidelines of this project
• I ran ESLint and other linters for modified files
• I have performed a self-review of my own code and tested it
• I have commented my code, particularly in hard-to-understand areas
  (including JSDoc for methods)
• My changes generate no new warnings
• My code needed automated testing. I have added them (this is optional task)

[louislam]

Unfortunately, I am working on this too, and the issue is actually more than just port numbers, because template variables could be everywhere in a yaml file.

Also there are existing dependencies that can parse and render environment variables into a file. I will show you later in a new pull request.

[syko9000]

No worries