Roll Xcode beta targets to Xcode16 B4

Also remove appending
__PLATFORMS__/iPhoneSimulator.platform/Developer/usr/lib/libXCTestBundleInject.dylib
to DYLD_INSERT_LIBRARIES in xctestrun for EG tests. As of Xcode16 Beta 4 the presence of that value for that environment variable began causing
the following error when attempting to launch EG tests:
'NSInternalInconsistencyException', reason: 'Cannot initiate shared
session more than once.'

1. it was initially added in:
https://codereview.chromium.org/2805133005
to enable running EG tests on device using the xcodebuild CLI.

2. xctestrun creation logic was moved from test_runner.py to
test_apps.py in:
https://chromium-review.googlesource.com/c/chromium/src/+/1961166
and during that move DYLD_INSERT_LIBRARIES went from
__PLATFORMS__/iPhoneOS.platform/Developer/usr/lib/libXCTestBundleInject.dylib
to
__PLATFORMS__/iPhoneSimulator.platform/Developer/usr/lib/libXCTestBundleInject.dylib

Since 2. even on-device EG tests are using that dylib from iPhoneSimulator.platform, which doesn't seem to be needed (or right).

Bug: 355030048
Change-Id: Ie461d5846696d5412e89db125953a4d93074096d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5738253
Reviewed-by: Justin Cohen <justincohen@chromium.org>
Commit-Queue: Will Yeager <wyeager@google.com>
Reviewed-by: Yue She <yueshe@google.com>
Cr-Commit-Position: refs/heads/main@{#1332961}