docs: update readme with requirements

### What does this PR do?

Updates the readme with requirements for vfkit / podman support

### Screenshot / video of UI

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screenshots or screencasts showing the difference -->

### What issues does this PR fix or reference?

<!-- Include any related issues from Podman Desktop
repository (or from another issue tracker). -->

Closes
podman-desktop#41
since it is now in podman 4.9

Closes
podman-desktop#40
as that release is out now

### How to test this PR?

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Signed-off-by: Charlie Drage <[email protected]>

README.md

@@ -39,13 +39,11 @@ To a bootable OS image format:
 
 Disclaimer: This is **EXPERIMENTAL** and all features are subject to change as we develop the extension.
 
-### Requirement 1. Be on macOS M1/M2/M3 (silicon)
+### Requirement 1. System requirements
 
-As of right now, this is being tested and only works on macOS silicon architecture.
-
-Use Windows / Linux / Mac (Intel-based) at your own risk.
-
-Windows & Linux support will be implemented in the future.
+* macOS M1/M2/M3 Silicon Architecture ONLY (Windows & Linux support coming soon)
+* [podman 4.9.0+](https://github.com/containers/podman/releases/tag/v4.9.0)
+* [vfkit 0.5.1+](https://github.com/crc-org/vfkit) for "one-click" VM launch button support
 
 ### Requirement 2. Rootful mode on Podman Machine