Created instructions to import from most providers (#2022)

## Description
Added detail to docs on what's able to be imported via the app

Give me a shout if anything needs updating!

docs/docs/auth/migration-guides/most-providers/index.md

@@ -0,0 +1,29 @@
+---
+title: Migrating from most providers
+description:
+    Guide for importing your existing 2FA tokens into Ente Auth from most providers
+---
+
+# Migrating from most providers
+
+---
+
+Ente Auth natively supports imports from many 2FA providers. In addition to the 
+providers specifically listed in the documentation, the supported providers are:
+
+-   2FAS Authenticator
+-   Aegis Authenticator
+-   Bitwarden
+-   Google Authenticator
+-   Ravio OTP
+-   LastPass
+
+Details as to how codes may be imported from these providers may be found within
+the app.
+
+Ente Auth also supports imports from Auth's own encrypted exports and plain 
+text files. Plain text files must be in the following format:
+
+```otpauth://totp/provider.com:you@email.com?secret=YOUR_SECRET```
+
+The codes can be seperated by a comma or a new line.