[M96][pdf] Disable flaking PDFExtensionTest.BasicPrintCommand

Disable the test on all platforms since it's flaking on all platforms.

Merging to M96 to de-noise M96 branch bots.

(cherry picked from commit 2b151a3c3b921fe0cca9bdc68d37cb387d4493d7)

Bug: 1258561
Change-Id: Ia33a1d94a5b561a3f89aa8031baf6c531233efce
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3216280
Auto-Submit: Daniel Hosseinian <dhoss@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Cr-Original-Commit-Position: refs/heads/main@{#930253}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3276790
Cr-Commit-Position: refs/branch-heads/4664@{#970}
Cr-Branched-From: 24dc4ee75e01a29d390d43c9c264372a169273a7-refs/heads/main@{#929512}

diff --git a/chrome/browser/pdf/pdf_extension_test.cc b/chrome/browser/pdf/pdf_extension_test.cc
index 2e5d7aa0..1101ea49 100644
--- a/chrome/browser/pdf/pdf_extension_test.cc
+++ b/chrome/browser/pdf/pdf_extension_test.cc

@@ -1664,7 +1664,8 @@
 
 }  // namespace
 
-IN_PROC_BROWSER_TEST_P(PDFExtensionTest, BasicPrintCommand) {
+// TODO(crbug.com/1258561): Fix flakes.
+IN_PROC_BROWSER_TEST_P(PDFExtensionTest, DISABLED_BasicPrintCommand) {
   content::WebContents* guest_contents =
       LoadPdfGetGuestContents(embedded_test_server()->GetURL("/pdf/test.pdf"));
   content::RenderFrameHost* frame = GetPluginFrame(guest_contents);