[EXTERNAL] Adds a convenience method to set the Amplitude User ID and Amplitude Device ID (#5425) via @alpennec (#5446)

* [EXTERNAL] Adds a convenience method to set the Amplitude User ID ($amplitudeUserId) and Amplitude Device ID ($amplitudeDeviceId) (#5425)

* Adding Amplitude UserID and DeviceID

* Add convenience method for setting Amplitude User ID and Amplitude Device ID

* fix lint

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Co-authored-by: Axel Le Pennec <alpennec@users.noreply.github.com>

Sources/DocCDocumentation/DocCDocumentation.docc/Purchases.md

@@ -113,6 +113,9 @@ Most features require configuring the SDK before using it.
 - ``Purchases/setMixpanelDistinctID(_:)``
 - ``Purchases/setMparticleID(_:)``
 - ``Purchases/setOnesignalID(_:)``
+- ``Attribution/setPostHogUserID(_:)``
+- ``Attribution/setAmplitudeUserID(_:)``
+- ``Attribution/setAmplitudeDeviceID(_:)``
 
 ### Advanced Configuration
 - ``Purchases/finishTransactions``

Sources/DocCDocumentation/DocCDocumentation.docc/RevenueCat.md

@@ -157,6 +157,9 @@ Or browse our iOS sample apps:
 - ``Purchases/setMixpanelDistinctID(_:)``
 - ``Purchases/setMparticleID(_:)``
 - ``Purchases/setOnesignalID(_:)``
+- ``Attribution/setPostHogUserID(_:)``
+- ``Attribution/setAmplitudeUserID(_:)``
+- ``Attribution/setAmplitudeDeviceID(_:)``
 
 ### Configuring the SDK with parameters (deprecated)
 - ``Purchases/configure(withAPIKey:appUserID:)-57pv0``