feat: sort responses for csv download according to creation date

[chowyiyin]

Problem

Currently, when a CSV of responses are downloaded (in storage mode), the responses are not sorted according to date. Refer to issue #1721

Closes #1721

Solution

The naive approach was adopted to solve this problem. Specifically Array.prototype.sort() was used to sort the responses. This solution seems satisfactory even for a large number of responses. When tested with 100,000 responses, the sorting duration ranged from 1 to 2 seconds. With approximately 500,000 responses, the sorting duration ranged from 9 to 10 seconds, which is not significant compared to the decryption duration of approximately 3 minutes. Throughout the download, the following modal is displayed and no obvious freezes or slowdowns in the spinner were observed. The short clip below shows the condition of the spinner before and during sorting.

csv_download.mov

Tests

• Submit responses to storage mode form and download CSV. Ensure downloaded CSV is sorted (oldest to newest)

[liangyuanruo]

As commented. It might also make sense to decouple the code into a standalone, mutable sort() instance method, instead of embedding it in process().

[mantariksh]

also to do the following:

• make a more conscious decision about what the upper limit of testing should be, and test on staging with this upper limit. 500,000 is a lot but if we expect that some users may download even more, we should ensure that the implementation is stable.
• test on staging with multiple browsers

[liangyuanruo]

• test on staging with multiple browsers

I think we can get away with testing on localhost, since code changes are client-side

[mantariksh]

I think we can get away with testing on localhost, since code changes are client-side

I'm not sure about this - doesn't machine performance play a factor? so we'd need to test on Chrome on GSIB before being sure that this works?

[liangyuanruo]

Sure, we can test on GSIB to be safe.

[mantariksh]

to populate a test form with 500k submissions and test performance on GSIB