* modified all references in docs module
* replaced in inline scala docs
* renamed variable and changed access specifier
* reanmed in remaining places
* Adjusted path (instead of `akka` used `pekko`)
* Where applicable akka.io is replaced with pekko.apache.org
* replaced akka with pekko in the path
* Removed TODO
* Removed migration guide to gRPC (there is no user using pekko at the moment so no need of migration guide)
* Added back migration to gRPC section
* removed TODO
* alpakka is replaced with pekko-connectors
* the Akka online documentation -> the Pekko online documentation
* referring akka security docs
* reffering to akka migration guides (pekko is not managing them)
* Using pekkoBaseURL for platform-guide.base_url
* removed unnecessary redirects and used current instead of 2.6
* Changed akka discovery to pekko discovery
* Some more replacement
* fix merge issue
* revert platform-guide change because we
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Co-authored-by: PJ Fanning <pjfanning@users.noreply.github.com>