[PLAT-8530] Fix incorrect device.time in 32-bit crash reports

[nickdowell]

Goal

Fix invalid timestamps in 32-bit crash reports caused by integer overflow.

Identified when adding E2E support for watchOS - #1398

tv_sec * 1000 was overflowing due to tv_sec (type: long) being 32-bit in ILP32 environments.

Changeset

Promotes tv_sec and tv_usec to long long (64 bit) when converting values to milliseconds.

Testing

Our E2E tests do not have any iOS or macOS 32-bit coverage, and attempts to add support are blocked:

• BrowserStack currently rejects iOS apps that don't include 64-bit support.
  A 32-bit-only build is needed for that slice to run on 64-bit devices (the only ones available).
• Building 32-bit code for macOS requires Xcode <= 9, which is not available in our build environment.
  https://developer.apple.com/documentation/xcode-release-notes/xcode-10-release-notes#Deprecations
  The macOS 10.14 SDK no longer contains support for compiling 32-bit applications.
  If developers need to compile for i386, Xcode 9.4 or earlier is required. (39858111)

Verified by running features/barebone_tests.feature:123 on Apple Watch.

[github-actions]

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