create module page for anPspParamsConverter module (prebid#5423)

* create module page for anPspParamsConverter module

* fix linting error

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Co-authored-by: Muki Seiler <[email protected]>

dev-docs/modules/anPspParamsConverter.md

@@ -0,0 +1,26 @@
+---
+layout: page_v2
+page_type: module
+title: Module - anPspParamsConverter
+description: Formats bid params for AppNexus PSP requests made through Prebid.js.
+module_code : apPspParamsConverter
+display_name : apPspParamsConverter
+enable_download : true
+sidebarType : 1
+---
+
+# anPspParamsConverter Module
+
+{:.no_toc}
+
+This module is a temporary measure for publishers running Prebid.js 9.0+ and using the AppNexus PSP endpoint through their Prebid.js setup. Please ensure to include this module in your builds of Prebid.js 9.0+, otherwise requests to PSP may not complete successfully.
+
+## Module's Purpose
+
+This module replicates certain functionality that was previously stored in the appnexusBidAdapter.js file within a function named transformBidParams.
+
+This transformBidParams was a standard function in all adapters, which helped to change/modify the params and their values to a format that matched the bidder's request structure on the server-side endpoint. In Prebid.js 9.0, this standard function was removed in all adapter files, so that the whole client-side file (eg appnexusBidAdapter.js) wouldn't have to be included in a prebid.js build file that was meant for server-side bidders.
+
+## How to use the module as a publisher
+
+There is no setConfig setup needed for this module.  Simply include this module in your Prebid.js build file if you plan to make requests to the AppNexus PSP endpoint through Prebid.js.