Timestamp-like strings lose quote

**What steps did you take:**

When I provide a string but contains timestamp, after templating with Ytt this strings lose the quote.
This would be valid, but yaml parsers handle this as a date not a string and convet it like Mon Sep 20 12:00:00 CEST 2021.
This happens even I turn on strict yaml, according to rule "requires strings with colon to be explicitly quoted"

template.yaml:
exampleTimestamp: "2023-01-01T07:00:00"

ytt -f template.yaml
ytt -f template.yaml -s

**What happened:**

exampleTimestamp: 2023-01-01T07:00:00

**What did you expect:**

exampleTimestamp: "2023-01-01T07:00:00"

**Environment:**

- ytt version (use `ytt --version`): ytt version 0.47.0
- OS (e.g. from `/etc/os-release`):
ProductName: macOS
ProductVersion: 14.2.1
BuildVersion: 23C71

---
Vote on this request

👍 "I would like to see this addressed as soon as possible"