diff-sequences

Upstream: https://github.com/facebook/jest/tree/v27.4.7/packages/diff-sequences

Compare items in two sequences to find a longest common subsequence.

---

$3

* :x: Property tests and performance tests from upstream are not included.
* :warning: Lua does not allow indexing into strings, the consumer is expected to handle the input types in isCommon and foundSubsequence.
* A stringToArray function is implemented to convert input strings to arrays for tests.
* Substring tests are done using arrays of characters instead. The substring comparison methods are omitted.
* Lua is 1 indexed so array indices are replaced with index + 1.
* Uses of NOT_YET_SET are replaced with just a 0 since this is a JS-specific workaround.
* Lua treats 0 as a true value so nChange || baDeltaLength needs to be written as nChange ~= 0 and nChange or baDeltaLength.