Adds some unit tests for the seeder's `parse_name()` function.
Currently, `parse_name()` has some logic flaws that prevent some test cases. These include:
- No check for the length of the query name (the maximum length is 255 characters total)
- An assumption that the length of the first label is less than the length of the output buffer
- An assumption that the length of the input string is greater than 0 (this shouldn't be a problem in practice as an empty string is not a valid name, but is worth noting for its undefined behavior).
Depends on D4417