For deno runtime load -s value as local file if non-http

[rwblair]

From #1930

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 0% with 9 lines in your changes missing coverage. Please review.

Project coverage is 87.61%. Comparing base (35306a2) to head (e95a5eb). Report is 13 commits behind head on master.

Files with missing lines	Patch %	Lines
bids-validator/src/setup/loadSchema.ts	0.00%	9 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #2166 +/- ## ========================================== + Coverage 85.73% 87.61% +1.88% ========================================== Files 91 133 +42 Lines 3785 7172 +3387 Branches 1220 1702 +482 ========================================== + Hits 3245 6284 +3039 - Misses 454 793 +339 - Partials 86 95 +9 ```

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[effigies]

Hmm. I'm actually able to load the schema with file://$HOME/Projects/bids/specification/src/schema.json before, but not now. I'm okay with not using file:///, and this works with that. Did you test with file:///?

[effigies]

❯ deno
Deno 2.0.3
exit using ctrl+d, ctrl+c, or close()
REPL is running with all permissions allowed.
To specify permissions, run `deno repl` with allow flags.
> fetch('file:///home/chris/Projects/bids/specification/src/schema.json')
Promise {
  Response {
    body: ReadableStream { locked: false },
    bodyUsed: false,
    headers: Headers {},
    ok: true,
    redirected: false,
    status: 200,
    statusText: "OK",
    url: "file:///home/chris/Projects/bids/specification/src/schema.json"
  }
}

[effigies]

@rwblair Please reopen on bids-validator.