refactor: large file removal

[AaronDabney]

There is a 10.5MB file checked into the commit history that is just the letter 'a' 10,485,760 times.

lib/common/tests/resources/large_file.bin

• Removed large_file.bin
• Added just in time large file generation/deletion for reliant unit tests
• Added test_file.bin to .gitignore to avoid mishaps
• added trailing newline to .gitignore

Normally removing a large file that's been checked in wouldn't shrink a git project very much but in this case it does because its easily compressible.

Recommend prior merge of testing harness upgrade: #394

Reference issue: #395

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[AaronDabney]

"If you are an Oracle employee, please make sure that you are a member of the main Oracle GitHub organization, and your membership in this organization is public."

I meet both of these criteria.