Mitigate the poor interaction between ndots expansion and non-path strings (#13218)

# Description

@hustcer reported that slashes were disappearing from external args
since #13089:

```
$> ossutil ls oss://abc/b/c
Error: invalid cloud url: "oss:/abc/b/c", please make sure the url starts with: "oss://"

$> ossutil ls 'oss://abc/b/c'
Error: oss: service returned error: StatusCode=403, ErrorCode=UserDisable, ErrorMessage="UserDisable", RequestId=66791EDEFE87B73537120838, Ec=0003-00000801, Bucket=abc, Object=
```

I narrowed this down to the ndots handling, since that does path parsing
and path reconstruction in every case. I decided to change that so that
it only activates if the string contains at least `...`, since that
would be the minimum trigger for ndots, and also to not activate it if
the string contains `://`, since it's probably undesirable for a URL.

Kind of a hack, but I'm not really sure how else we decide whether
someone wants ndots or not.

# User-Facing Changes
- bare strings not containing ndots are not modified
- bare strings containing `://` are not modified

# Tests + Formatting
Added tests to prevent regression.

0 files changed, 0 insertions, 0 deletions