Asterio docs: add bidder documentation (#6521)

* Asterio docs: add bidder documentation

* Asterio docs: fix markdownlint issues

* Asterio docs: simplify table formatting

* Asterio docs: add meta data

* Update dev-docs/bidders/asterio.md

Co-authored-by: Muki Seiler <muuki88@users.noreply.github.com>

---------

Co-authored-by: Muki Seiler <muuki88@users.noreply.github.com>

Author: mihanikw2g

dev-docs/bidders/asterio.md

@@ -0,0 +1,78 @@
+---
+layout: bidder
+title: Asterio
+description: Prebid Asterio Bidder Adapter
+biddercode: asterio
+pbjs: true
+pbs: false
+media_types: banner, video
+tcfeu_supported: false
+dsa_supported: false
+gvl_id: none
+usp_supported: false
+coppa_supported: false
+gpp_sids: none
+schain_supported: true
+dchain_supported: false
+userId: none
+safeframes_ok: false
+deals_supported: true
+floors_supported: true
+fpd_supported: false
+prebid_member: false
+multiformat_supported: will-bid-on-any
+ortb_blocking_supported: partial
+sidebarType: 1
+---
+
+## Bid Params
+
+{: .table .table-bordered .table-striped }
+
+| Name | Scope | Description | Example | Type |
+| --- | --- | --- | --- | --- |
+| `adUnitToken` | required | Ad unit token provided by Asterio. | `'xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx'` | `string` |
+| `pos` | optional | Ad position hint. Allowed values follow OpenRTB position conventions, e.g. above the fold: `1`, below the fold: `3`, middle of the fold: `7`. | `1` | `integer` |
+
+## Banner Test Ad Unit
+
+```javascript
+var adUnits = [{
+  code: 'test-banner',
+  mediaTypes: {
+    banner: {
+      sizes: [[300, 250]]
+    }
+  },
+  bids: [{
+    bidder: 'asterio',
+    params: {
+      adUnitToken: 'xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx'
+    }
+  }]
+}];
+```
+
+## Video Test Ad Unit
+
+```javascript
+var adUnits = [{
+  code: 'test-video',
+  mediaTypes: {
+    video: {
+      context: 'outstream',
+      playerSize: [640, 360],
+      mimes: ['video/mp4'],
+      protocols: [2, 3],
+      playbackmethod: [2],
+      plcmt: 4
+    }
+  },
+  bids: [{
+    bidder: 'asterio',
+    params: {
+      adUnitToken: 'xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx'
+    }
+  }]
+}];
+```