[V4RB]Diagnose report file stay in use until I quit

[Erik Mueller-Harder]

OK, this is definitely a problem with Rb 5.2.1, V4RB 1.9.8, and OS X 10.2.6, too:

Francois Van Lerberghe wrote:

> Without quitting your app,
> - trash the file and try to empty the trash.

We failed this test -- file was in use.

> - open the file with a text editor (BBEdit) and try to save some
>   changes.

We failed this test, too:  "This file could not be opened with the requested permissions (Mac OS Error code -54)."

-- Erik