Update documentation to specify what kind of thing an ID or DESCRIPTION is

**What would you like to be added**:

A lot of yardstick commands accept something like `DESCRIPTION` or `ID`, but it's not obvious what this string is. Example:

```
❯ yardstick label explore --help
Usage: yardstick label explore [OPTIONS] DESCRIPTION

interact with an label results for a single image scan

Options:
-y, --year-max-limit TEXT max year to include in comparison (relative
to the CVE ID)
-c, --derive-year-from-cve-only
only use the CVE ID year-max-limit
--help Show this message and exit.
```

In this case, `DESCRIPTION` is really a result set UUID obtained by running `yardstick result list` and looking for the image+tool combo the user is interested in. But nothing about `DESCRIPTION` makes it obvious what to pass in our how to get it.

**Why is this needed**:

The use of generic parameter names like `ID` and `DESCRIPTION` in the docs makes it very hard to come up to speed in yardstick.

**Additional context**:

Start by running `yardstick label explore --help` and `yardstick result list` to trace how the result set UUID is obtained and represented. Review the help and documentation for commands using generic `ID` or `DESCRIPTION` arguments; done means those parameters identify what to pass and how to obtain it, including the label-explore example.

Written by the indexing model from the issue text.