Update text/0000-edition-2021.md

Co-authored-by: Eric Huss <[email protected]>

Author: nikomatsakis

text/0000-edition-2021.md

@@ -129,7 +129,7 @@ The expected workflow for upgrading to a new edition is as follows:
 
 ## Specifying edition changes and migration plans
 
-Any RFC or other proposal that will cause code that used to compile on edition `N` no longer compiles on edition `N+1` must include detais of how the "current edition" for that change is determined as well a migration plan. 
+Any RFC or other proposal that will cause code that used to compile on edition `N` no longer compiles on edition `N+1` must include details of how the "current edition" for that change is determined as well a migration plan. 
 
 ### Determining the current edition