Failure to remove obsolete file when nameclass changes

**Describe the bug**
When the nameclass of an item has changed outside the editor, the file extension changes, but Link fails to notice the presence of the old file.

**To Reproduce**
```none
]link.create # /tmp/nc-change
Linked: # ←→ c:\tmp\nc-change [directory was created]
⎕FX'foo' '∘∘∘'
]link.add foo
Added: #.foo
⎕EX'foo'
foo←⍳3
]link.add foo
Added: #.foo
↑⊃⎕ninfo⍠1⊢'/tmp/nc-change/*'
/tmp/nc-change/foo.apla
/tmp/nc-change/foo.aplf
```
**Expected behaviour**
It should remove the orphaned file.

**Session transcript**
If applicable, copy your log in to help explain your problem.

**Desktop (please complete the following information):**
- OS: Windows
- APL version: 19.0.47359 64-bit Unicode
- `⎕SE.Link.Version`: 4.0.7