[JS] the replace statement in parseDate is too greedy (#8632)

[tray2100]

Fix for #8632

• updated the regex used in the String.replace for parseDate() to more precisely target ISO-8601
• added the replace function call to the ES6 mustache file

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@jfiala @wing328

[wing328]

CircleCI tests passed via https://app.circleci.com/pipelines/github/OpenAPITools/openapi-generator/8681/workflows/5c157229-9edc-45cd-ae79-6067202ea5a2/jobs/22257

[wing328]

@tray2100 thanks for the PR, which has been included in the v5.1.0 release: https://twitter.com/oas_generator/status/1373636654024380423

[PetrPy]

The parseDate function does not work in Safari, tested on version 14.1.1 (16611.2.7.1.4).

The following:

new Date("2021-05-28 18:57:50.843933")

works well in Chrome, but Safari requires the "T" letter to be included as a separator of date and time parts. However, the following would work in both browsers:

new Date("2021-05-28T18:57:50.843933")    // note the T letter

I suggest that the command:

return new Date(str.replace(/(\d)(T)(\d)/i, '$1 $3'));

is simply replaced with:

return new Date(str);