Fix runner use of moleculer.config function with default export

[shawnmcknight]

📝 Description

When using moleculer-runner and a specified moleculer.config.<ext> file it should support both of the following:

• Use of default export syntax
• Exporting a function that returns a configuration object

The current flow of the runner is checking if the required moleculer.config.<ext> is a function prior to the logic which determines if the configuration file has a default export. This prevents the function from being executed if it is a default export.

This PR makes the following changes:

• Always return a configuration object from loadConfigFile even if a configuration file was not found
• Pass the configuration object returned from loadConfigFile to mergeOptions
• Use the passed configuration object in mergeOptions instead of this.configFile
• Eliminate use of this.configFile
• Change the order of processing in loadConfigFile so that the default export check precedes the function check and execution
• Adds support for .mts suffixes to the esm runner
• Adds new moleculer.config.async.ts and moleculer.config.ts files to the runner examples which validate typescript configurations and default exports for use with the runner

💎 Type of change

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

🚦 How Has This Been Tested?

Tested using the newly created runner examples as well as the existing examples for both cjs and esm variants.

🏁 Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• I have commented my code, particularly in hard-to-understand areas

[icebob]

Good job, thanks!