Fix a css-paint-api/ layout test failure

This CL fixes a failing layout test dynamic-import.html. The problem
with it is that all the file name under css-paint-api/ needs to be
foo.https.html so that our test infra knows that it should spin up
an https server to run that test. The failing test doesn't have the
right suffix and that's why.

This Cl simply rename the test and it should be good.

Bug: 1157960
Change-Id: I3cdad68715eb0289b4a8707fa1d4c8a63421e031
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2606483
Commit-Queue: Xida Chen <xidachen@chromium.org>
Reviewed-by: Yi Gu <yigu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#840031}

third_party/blink/web_tests/TestExpectations

@@ -3093,10 +3093,6 @@ crbug.com/1034807 [ Linux ] virtual/off-main-thread-css-paint/external/wpt/css/c
 crbug.com/1034807 [ Mac ] virtual/off-main-thread-css-paint/external/wpt/css/css-paint-api/paint2d-gradient.https.html [ Failure ]
 crbug.com/1034807 [ Win ] virtual/off-main-thread-css-paint/external/wpt/css/css-paint-api/paint2d-gradient.https.html [ Failure ]
 
-# WPT css-paint-api tests failing, possibly for the same reason as above
-crbug.com/1157960 external/wpt/css/css-paint-api/dynamic-import.html [ Failure ]
-crbug.com/1157960 virtual/off-main-thread-css-paint/external/wpt/css/css-paint-api/dynamic-import.html [ Failure ]
-
 crbug.com/829028 external/wpt/css/css-break/avoid-border-break.html [ Failure ]
 crbug.com/829028 external/wpt/css/css-break/borders-000.html [ Failure ]
 crbug.com/829028 external/wpt/css/css-break/borders-001.html [ Failure ]