Remove invalid releases automatically (#466)

Automatically remove empty releases or releases which are released in the future, regardless of the product.

Also refactored a bit releasedata.py to use better names and clarify types.

releases/amazon-linux.json

@@ -1,57 +1,5 @@
 {
-  "releases": {
-    "2023": {
-      "name": "2023"
-    },
-    "2018.03": {
-      "name": "2018.03"
-    },
-    "2017.09": {
-      "name": "2017.09"
-    },
-    "2017.03": {
-      "name": "2017.03"
-    },
-    "2016.09": {
-      "name": "2016.09"
-    },
-    "2016.03": {
-      "name": "2016.03"
-    },
-    "2015.09": {
-      "name": "2015.09"
-    },
-    "2015.03": {
-      "name": "2015.03"
-    },
-    "2014.09": {
-      "name": "2014.09"
-    },
-    "2014.03": {
-      "name": "2014.03"
-    },
-    "2013.09": {
-      "name": "2013.09"
-    },
-    "2013.03": {
-      "name": "2013.03"
-    },
-    "2012.09": {
-      "name": "2012.09"
-    },
-    "2012.03": {
-      "name": "2012.03"
-    },
-    "2011.09": {
-      "name": "2011.09"
-    },
-    "2010.11": {
-      "name": "2010.11"
-    },
-    "2": {
-      "name": "2"
-    }
-  },
+  "releases": {},
   "versions": {
     "2023.7.20250623.1": {
       "name": "2023.7.20250623.1",