Add Web Animations 2 and CSS Fonts 5 (#290)

Follows from discussions in:
#279 (comment)

The specs are flagged with a "not ready for implementation" banner, but already
documented in BCD in practice, and implemented in at least one browser.

specs.json

@@ -13,6 +13,7 @@
   "https://drafts.csswg.org/css-backgrounds-4/ delta",
   "https://drafts.csswg.org/css-env-1/",
   "https://drafts.csswg.org/css-extensions-1/",
+  "https://drafts.csswg.org/css-fonts-5/ delta",
   {
     "url": "https://drafts.csswg.org/css-gcpm-4/",
     "seriesComposition": "delta",
@@ -33,6 +34,7 @@
   },
   "https://drafts.csswg.org/css-transitions-2/ delta",
   "https://drafts.csswg.org/scroll-animations-1/",
+  "https://drafts.csswg.org/web-animations-2/ delta",
   {
     "url": "https://drafts.fxtf.org/compositing-2/",
     "shortTitle": "Compositing 2"

src/data/monitor.json

@@ -318,10 +318,6 @@
       "comment": "Placholder for an eventual CSS Block Layout Level 3 Module",
       "lastreviewed": "2021-05-01"
     },
-    "https://drafts.csswg.org/web-animations-2/": {
-      "comment": "Marked as unofficial proposal",
-      "lastreviewed": "2021-05-01"
-    },
     "https://drafts.csswg.org/css-floats-3/": {
       "comment": "No spec yet",
       "lastreviewed": "2021-05-01"
@@ -346,10 +342,6 @@
       "comment": "Marked as not ready for implementation",
       "lastreviewed": "2021-05-01"
     },
-    "https://drafts.csswg.org/css-fonts-5/": {
-      "comment": "Marked as not ready for implementation",
-      "lastreviewed": "2021-05-01"
-    },
     "https://drafts.csswg.org/css-contain-3/": {
       "comment": "Marked as Exploratory Working Draft and empty for now",
       "lastreviewed": "2021-05-01"