Reenabled github page edit link (#3491)

# Description of Changes

The GitHub edit links were disabled in the new docs, this reenables
them.

# API and ABI breaking changes

None

# Expected complexity level and risk

1

# Testing

<!-- Describe any testing you've done, and any testing you'd like your
reviewers to do,
so that you're confident that all the changes work as expected! -->

- [x] Tested locally that this works.

docs/docusaurus.config.ts

@@ -93,6 +93,7 @@ const config: Config = {
       'classic',
       {
         docs: {
+          editUrl: "https://github.com/clockworklabs/SpacetimeDB/edit/master/docs/",
           routeBasePath: '/',
           sidebarPath: './sidebars.ts',
           sidebarCollapsed: false,

docs/package.json

@@ -16,6 +16,7 @@
   },
   "dependencies": {
     "@docusaurus/core": "3.9.1",
+    "@docusaurus/plugin-content-docs": "^3.9.2",
     "@docusaurus/preset-classic": "3.9.1",
     "@docusaurus/theme-common": "^3.9.1",
     "@easyops-cn/docusaurus-search-local": "^0.49.2",

docs/src/css/custom.css

@@ -299,10 +299,6 @@ strong {
   color: var(--clockworklabs-strong-color);
 }
 
-footer {
-  display: none;
-}
-
 .tabs__item {
   border-bottom-width: 1px;
 }