[receiver/mongodbatlas] Refactored to use New metric builder

[cpheps]

Description: Used latest version of mdatagen on mongodbatlas receiver and updated scraper code to utilize generated structures while trying to leave the majority of code intact where possible.

Not all metric and resource attributes where captures in the metadata.yaml so I updated that. I also renamed some resource attributes so they are all prefixed with mongodb_atlas where before only some where.

Link to tracking Issue:
Resolves #7145
Resolves #8831

Testing: Current tests still pass. Manually compared results against previous results before change and matches according (minus some resource property name changes)

Documentation: Generated metric docs have changed.

[cpheps]

@zenmoto Would you mind giving a review since you are codeowner?

[zenmoto]

That is a dramatic improvement.

[cpheps]

@dmitryax Can I get a re-review on this please?

[dmitryax]

Sorry for the late response

[dmitryax]

My idea for the switch case was to avoid passing functions. Something like this:

for _, point := range meas.DataPoints {
    if point.Value != nil {
        curTime, err := time.Parse(time.RFC3339, point.Timestamp)
        if err != nil {
            return err
        }
        record(mb, meas, point, curTime)
    }
}

And inside record we use switch case to make particular call.

Not needed for this PR tho. Can be done separately.