Add api page (#32)

# Changes

- Added [redocusaurus](https://github.com/rohit-gohri/redocusaurus) package to display swagger api with reference to [woodpecker](https://github.com/woodpecker-ci/woodpecker/tree/master/docs)
- Change `sed` for swagger.json for proper version and baseurl.
- Add a dropdown for different api versions. (screenshot below)
- On API pages, only API version dropdown will show(hide locale dropdown, version dropdown for doc, and doc search)
- Allow build CSR API pages for development so it saves building time.

# Screenshots

![Screen Shot 2023-06-27 at 11.56.59](/attachments/7f43976d-f9f1-42ff-85f5-0bc84e549441)

![Screen Shot 2023-06-27 at 10.58.11](/attachments/bde25da5-b0a6-4908-9c69-c6aed41f8f59)

![Screen Shot 2023-06-21 at 12.26.26](/attachments/84a9bf5a-229b-4031-9654-3bae6cb3301a)

![Screen Shot 2023-06-19 at 16.34.33](/attachments/653b2b59-bc8a-4e6c-82f2-eb9710f55d8d)

Search:

![Screen Shot 2023-06-21 at 14.49.15](/attachments/3a09bd89-36a8-4156-a2df-2d3176d3ddb1)

Reviewed-on: https://gitea.com/gitea/gitea-docusaurus/pulls/32
Co-authored-by: HesterG <hestergong@gmail.com>
Co-committed-by: HesterG <hestergong@gmail.com>

package.json

@@ -5,7 +5,9 @@
   "scripts": {
     "docusaurus": "docusaurus",
     "start": "docusaurus start",
+    "start-CSRApi": "cross-env INCLUDE_API='false' docusaurus start",
     "build": "docusaurus build",
+    "build-CSRApi": "cross-env INCLUDE_API='false' docusaurus build",
     "swizzle": "docusaurus swizzle",
     "deploy": "docusaurus deploy",
     "clear": "docusaurus clear",
@@ -21,10 +23,12 @@
     "clsx": "^1.2.1",
     "prism-react-renderer": "^1.3.5",
     "react": "^17.0.2",
-    "react-dom": "^17.0.2"
+    "react-dom": "^17.0.2",
+    "redocusaurus": "^1.6.3"
   },
   "devDependencies": {
-    "@docusaurus/module-type-aliases": "^2.3.1"
+    "@docusaurus/module-type-aliases": "^2.3.1",
+    "cross-env": "^7.0.3"
   },
   "browserslist": {
     "production": [