[AW] Use temp dir in devui ComponentsInfoLoaderTests

Change ComponentsInfoLoader to accept an arbitrary directory in the
constructor instead of using the components download directory by
default, in tests use a temp directory that is created before each test
and deleted after each test. This way we can avoid test flakes due to
async writes to the shared ComponentsInfoLoader directory from previous
tests. This is a speculative fix.

Bug: 1282188
Test: bin/run_webview_instrumentation_test_apk -f "*ComponentsInfoLoaderTest*"
Change-Id: I0caa96570c8990e6ca0dbbd20950306a2b0a417b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3352375
Reviewed-by: Nate Fischer <ntfschr@chromium.org>
Commit-Queue: Hazem Ashmawy <hazems@chromium.org>
Cr-Commit-Position: refs/heads/main@{#953636}