Remove broken showcase sites (#3536)

Co-authored-by: Adammatthiesen <[email protected]>
Co-authored-by: HiDeoo <[email protected]>

Author: 3 people

docs/src/assets/showcase/astro-ghostcms.xyz.png

@@ -32,11 +32,6 @@ import FluidGrid from './fluid-grid.astro';
 		thumbnail="starter.obytes.com.jpg"
 	/>
 	<Card title="Kanri" href="https://kanriapp.com" thumbnail="kanriapp.com.png" />
-	<Card
-		title="VRCFR Creator"
-		href="https://dev.vrchatfrance.fr"
-		thumbnail="dev.vrchatfrance.fr.png"
-	/>
 	<Card title="Refact" href="https://docs.refact.ai/" thumbnail="refact.ai.png" />
 	<Card
 		title="Some drops of PHP Book"
@@ -80,11 +75,6 @@ import FluidGrid from './fluid-grid.astro';
 		href="https://astro-snipcart.vercel.app/"
 		thumbnail="astro-snipcart.png"
 	/>
-	<Card
-		title="Astro-GhostCMS"
-		href="https://astro-ghostcms.xyz/"
-		thumbnail="astro-ghostcms.xyz.png"
-	/>
 	<Card title="oneRepo" href="https://onerepo.tools" thumbnail="onerepo.tools.png" />
 	<Card title="Flojoy" href="https://docs.flojoy.ai" thumbnail="docs.flojoy.ai.png" />
 	<Card title="AstroNvim" href="https://docs.astronvim.com" thumbnail="docs.astronvim.com.png" />
@@ -149,11 +139,6 @@ import FluidGrid from './fluid-grid.astro';
 		thumbnail="developers.cloudflare.com.png"
 	/>
 	<Card title="Yumma CSS" href="https://www.yummacss.com/" thumbnail="yummacss.com.png" />
-	<Card
-		title="RyzeKit Astro SaaS Starter"
-		href="https://docs.ryzekit.com/"
-		thumbnail="docs.ryzekit.com.png"
-	/>
 	<Card title="Open {re}Source" href="https://openresource.dev" thumbnail="openresource.dev.png" />
 	<Card
 		title="Orbit CSS"