Remove legacy.astroFlavoredMarkdown (#5771)

* Remove legacy.astroFlavoredMarkdown

* update vue mdx test

* Add a changeset

Author: matthewp

.changeset/grumpy-days-yell.md

@@ -0,0 +1,9 @@
+---
+'astro': major
+---
+
+Removes support for astroFlavoredMarkdown
+
+In 1.0 Astro moved the old Astro Flavored Markdown (also sometimes called Components in Markdown) to a legacy feature. This change removes the `legacy.astroFlavoredMarkdown` option completely.
+
+In 2.0 this feature will not be available in Astro at all. We recommend migration to MDX for those were still using this feature in 1.x.

packages/astro/e2e/fixtures/preact-compat-component/astro.config.mjs

@@ -3,8 +3,5 @@ import preact from '@astrojs/preact';
 
 // https://astro.build/config
 export default defineConfig({
-	legacy: {
-		astroFlavoredMarkdown: true,
-	},
 	integrations: [preact({ compat: true })],
 });

packages/astro/e2e/fixtures/preact-compat-component/src/pages/markdown.md

@@ -4,8 +4,5 @@ import mdx from '@astrojs/mdx';
 
 // https://astro.build/config
 export default defineConfig({
-	legacy: {
-		astroFlavoredMarkdown: true,
-	},
 	integrations: [preact(), mdx()],
 });

packages/astro/e2e/fixtures/preact-component/astro.config.mjs

@@ -4,8 +4,5 @@ import mdx from '@astrojs/mdx';
 
 // https://astro.build/config
 export default defineConfig({
-	legacy: {
-		astroFlavoredMarkdown: true,
-	},
 	integrations: [react(), mdx()],
 });

packages/astro/e2e/fixtures/preact-component/src/pages/markdown.md

@@ -4,8 +4,5 @@ import solid from '@astrojs/solid-js';
 
 // https://astro.build/config
 export default defineConfig({
-	legacy: {
-		astroFlavoredMarkdown: true,
-	},
 	integrations: [solid(), mdx()],
 });

packages/astro/e2e/fixtures/react-component/astro.config.mjs

@@ -4,8 +4,5 @@ import mdx from '@astrojs/mdx';
 
 // https://astro.build/config
 export default defineConfig({
-	legacy: {
-		astroFlavoredMarkdown: true,
-	},
 	integrations: [svelte(), mdx()],
 });