Remove "nightly" from installation instructions

[janek]

Description

Why

Installation instructions, when ran as they are now, currently produce the following error for me:

No compatible version of react-native-windows found.
  The latest supported version is react-native-windows@0.73.3.
  Please modify your application to use react-native@^0.73 or another supported version of react-native and try again.

NoAutoMatchingReactNativeWindows:
  No compatible version of react-native-windows found.
  The latest supported version is react-native-windows@0.73.3.
  Please modify your application to use react-native@^0.73 or another supported version of react-native and try again.

Just running the react-native "init" without pointing to a nightly version works for me. I've also reproduced the error and the solution on another system (with another OS).

Microsoft Reviewers: Open in CodeFlow

[jonthysell]

Thanks for your PR, but the doc files under the docs/ folder are for the "next" version of RNW, and nightly is appropriate there. However, you're right, it shouldnt' say nightly to use the current latest version, 0.73. I've updated the correct docs in your PR.

[janek]

Thank you very much!

[jonthysell]

@microsoft-github-policy-service rerun

[janek]

@microsoft-github-policy-service agree