Fix null being passed to g_path_get_dirname when probing in wasm

[kg]

Somewhat recently the module probing logic started passing null to g_path_get_dirname in some cases. While this wouldn't crash, it would print an error to the console.

cc @lambdageek

[ghost]

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Issue Details

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Somewhat recently the module probing logic started passing null to g_path_get_dirname in some cases. While this wouldn't crash, it would print an error to the console.

cc @lambdageek

Author:	kg
Assignees:	-
Labels:	arch-wasm
Milestone:	-

[lambdageek]

nit1: indentation

nit2: (I realize this was on the old version - we should clean it up) a & b && c is kind of sus. (a & b) != 0 && c is better.

[pavelsavara]

Does this fix #60392 ?

[ilonatommy]

Fixes #60392

[lewing]

/backport to release/6.0-staging

[github-actions]

Started backporting to release/6.0-staging: https://github.com/dotnet/runtime/actions/runs/4683579945