docs: update 7gui example links (#6052)

site/content/examples/20-7guis/01-7guis-counter/App.svelte

@@ -1,7 +1,7 @@
+<!-- https://eugenkiss.github.io/7guis/tasks#counter -->
 <script>
 	let count = 0;
 </script>
 
-<!-- https://github.com/eugenkiss/7guis/wiki#counter -->
 <input type=number bind:value={count}>
 <button on:click="{() => count += 1}">count</button>

site/content/examples/20-7guis/02-7guis-temperature/App.svelte

@@ -1,4 +1,4 @@
-<!-- https://github.com/eugenkiss/7guis/wiki#temperature-converter -->
+<!-- https://eugenkiss.github.io/7guis/tasks/#temp -->
 <input value={c} on:input="{e => setBothFromC(e.target.value)}" type=number> °c =
 <input value={f} on:input="{e => setBothFromF(e.target.value)}" type=number> °f
 

site/content/examples/20-7guis/03-7guis-flight-booker/App.svelte

@@ -1,3 +1,4 @@
+<!-- https://eugenkiss.github.io/7guis/tasks/#flight -->
 <script>
 	const tomorrow = new Date(Date.now() + 86400000);
 
@@ -44,7 +45,6 @@
 	}
 </style>
 
-<!-- https://github.com/eugenkiss/7guis/wiki#flight-booker -->
 <select bind:value={isReturn}>
 	<option value={false}>one-way flight</option>
 	<option value={true}>return flight</option>