bump happy-dom, disable all JS&c when parsing

version 10 didn't quite support disabling all of that

I have tested that `MfmService` (the other code that uses `happy-dom`)
still works fine: the RSS feed for a user is generated correctly, with
HTML rendered from MFM

pnpm-lock.yaml

@@ -257,8 +257,8 @@ importers:
         specifier: 14.4.2
         version: 14.4.2
       happy-dom:
-        specifier: 10.0.3
-        version: 10.0.3
+        specifier: 15.6.1
+        version: 15.6.1
       hpagent:
         specifier: 1.2.0
         version: 1.2.0
@@ -7671,6 +7671,10 @@ packages:
   happy-dom@10.0.3:
     resolution: {integrity: sha512-WkCP+Z5fX6U5PY+yHP3ElV5D9PoxRAHRWPFq3pG9rg/6Hjf5ak7dozAgSCywsTRUq2qfa8vV8OQvUy5pRXy8EQ==}
 
+  happy-dom@15.6.1:
+    resolution: {integrity: sha512-dsMHLsJHZYhXeExP47B2siAfKNVxptlwFss3/bq/9sG3iBt0P2WYFBq68JgMR5vB5gsN2Ev0feTTPD/+rosUNQ==}
+    engines: {node: '>=18.0.0'}
+
   hard-rejection@2.1.0:
     resolution: {integrity: sha512-VIZB+ibDhx7ObhAe7OVtoEbuP4h/MuOTHJ+J8h/eBXotJYl0fBgR72xDFCKgIh22OJZIOVNxBMWuhAr10r8HdA==}
     engines: {node: '>=6'}
@@ -20175,6 +20179,12 @@ snapshots:
       whatwg-encoding: 2.0.0
       whatwg-mimetype: 3.0.0
 
+  happy-dom@15.6.1:
+    dependencies:
+      entities: 4.5.0
+      webidl-conversions: 7.0.0
+      whatwg-mimetype: 3.0.0
+
   hard-rejection@2.1.0: {}
 
   has-bigints@1.0.2: {}