Link from $host directive docs to custom elements docs (#15686)

Author: jamesscottbrown

Diff for: documentation/docs/02-runes/08-$host.md

@@ -2,7 +2,7 @@
 title: $host
 ---
 
-When compiling a component as a custom element, the `$host` rune provides access to the host element, allowing you to (for example) dispatch custom events ([demo](/playground/untitled#H4sIAAAAAAAAE41Ry2rDMBD8FSECtqkTt1fHFpSSL-ix7sFRNkTEXglrnTYY_3uRlDgxTaEHIfYxs7szA9-rBizPPwZOZwM89wmecqxbF70as7InaMjltrWFR3mpkQDJ8pwXVnbKkKiwItUa3RGLVtk7gTHQXRDR2lXda4CY1D0SK9nCUk0QPyfrCovsRoNFe17aQOAwGncgO2gBqRzihJXiQrEs2csYOhQ-7HgKHaLIbpRhhBG-I2eD_8ciM4KnnOCbeE5dD2P6h0Dz0-Yi_arNhPLJXBtSGi2TvSXdbpqwdsXvjuYsC1veabvvUTog2ylrapKH2G2XsMFLS4uDthQnq2t1cwKkGOGLvYU5PvaQxLsxOkPmsm97Io1Mo2yUPF6VnOZFkw1RMoopKLKAE_9gmGxyDFMwMcwN-Bx_ABXQWmOtAgAA)):
+When compiling a component as a [custom element](custom-elements), the `$host` rune provides access to the host element, allowing you to (for example) dispatch custom events ([demo](/playground/untitled#H4sIAAAAAAAAE41Ry2rDMBD8FSECtqkTt1fHFpSSL-ix7sFRNkTEXglrnTYY_3uRlDgxTaEHIfYxs7szA9-rBizPPwZOZwM89wmecqxbF70as7InaMjltrWFR3mpkQDJ8pwXVnbKkKiwItUa3RGLVtk7gTHQXRDR2lXda4CY1D0SK9nCUk0QPyfrCovsRoNFe17aQOAwGncgO2gBqRzihJXiQrEs2csYOhQ-7HgKHaLIbpRhhBG-I2eD_8ciM4KnnOCbeE5dD2P6h0Dz0-Yi_arNhPLJXBtSGi2TvSXdbpqwdsXvjuYsC1veabvvUTog2ylrapKH2G2XsMFLS4uDthQnq2t1cwKkGOGLvYU5PvaQxLsxOkPmsm97Io1Mo2yUPF6VnOZFkw1RMoopKLKAE_9gmGxyDFMwMcwN-Bx_ABXQWmOtAgAA)):
 
 <!-- prettier-ignore -->
 ```svelte