Update roadmap after 1.0.0-alpha.1 release (apollographql#2145)

Author: calvincestari

ROADMAP.md

@@ -1,4 +1,4 @@
-# Apollo iOS Roadmap - _Last Updated December 2021_
+# Apollo iOS Roadmap - _Last Updated February 2022_
 
 _If this document has not been updated within the past three months, please [file an issue](https://github.com/apollographql/apollo-ios/issues/new/choose) asking the [maintainers](https://github.com/apollographql/apollo-ios#maintainers) to update it._
 
@@ -13,7 +13,9 @@ These are the three guiding principles we aim for in each major release:
 - **Completeness**: There are three main parts to the SDK: code generation, network fetching/parsing, and caching. These must provide enough functionality to be a good foundation for incremental improvements within major releases without requiring breaking changes.
 - **Clarity**: Everything must be clearly documented with as many working samples as possible.
 
-## 1.0 - _Estimated Alpha release by end of Q4 2021_
+## 1.0 - _Continuing with Alpha releases_
+
+[Alpha 1 is available](https://github.com/apollographql/apollo-ios/releases/tag/1.0.0-alpha.1), please try it and give us your feedback.
 
 These are the major initiatives planned for 1.0/1.x:
 - **Swift-based Codegen**: The code generation is being rewritten with a Swift-first approach instead of relying on scripting and Typescript. This will allow easier community contribution to code generation and provide the opportunity to improve various characteristics such as generated code size and performance.