fix: change comment to be JSON valid

[spouliot]

GitHub Issue (If applicable): closes #767

PR Type

What kind of change does this PR introduce?

• Bugfix

What is the current behavior?

The global.json file used for templates is NOT valid JSON - since comments are not allowed in the format.

What is the new behavior?

Comment was changed to fit the JSON format.

PR Checklist

Please check if your PR fulfills the following requirements:

• [x] Associated with an issue (GitHub or internal)

Other information

Internal Issue (If applicable):

[jojorne]

Comments in global.json files are supported using JavaScript or C# style comments. - Comments in global.json

If all, I'd just break it into multiple lines to make it easier to read:

{
  // To update the version of Uno please update the version of the Uno.Sdk here.
  // See https://aka.platform.uno/upgrade-uno-packages for more information.
  "msbuild-sdks": {
    "Uno.Sdk": "$UnoSdkVersion$"
  }
}

[jeromelaban]

@mergifyio backport release/stable/5.2

[mergify[bot]]

backport release/stable/5.2

🟠 Waiting for conditions to match

- [ ] `merged` [📌 backport requirement]

[jeromelaban]

@mergifyio backport release/stable/5.3

[mergify[bot]]

backport release/stable/5.3

🟠 Waiting for conditions to match

- [ ] `merged` [📌 backport requirement]

[jeromelaban]

Let's not merge this one, we'll use the jsonc config.