docs(contracts): update unstaking period

Author: mattstam

contracts/.env.example

@@ -30,7 +30,7 @@ MAX_UNSTAKE_REQUESTS=10
 ### be greater than the longest length that a VApp `step` can be delayed by.
 ###
 ### Immutable after deployment.
-UNSTAKE_PERIOD=1814400 # 21 days
+UNSTAKE_PERIOD=1209600 # 14 days
 
 ### The minimum delay (in seconds), plus governance parameters, for a slash request to be cancelled.
 ###