[GHC] #14166: Typo Fix `necssary`

[GHC]

#14166: Typo Fix `necssary`
-------------------------------------+-------------------------------------
           Reporter:  h4ck3rm1k3     |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  lowest         |         Milestone:
          Component:  Compiler       |           Version:  8.2.1
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  Documentation
  Unknown/Multiple                   |  bug
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
-------------------------------------+-------------------------------------
 https://github.com/ghc/ghc/pull/72

 diff --git a/compiler/hsSyn/HsExpr.hs b/compiler/hsSyn/HsExpr.hs
 index 1bde776..f75cc2c 100644
 --- a/compiler/hsSyn/HsExpr.hs
 +++ b/compiler/hsSyn/HsExpr.hs
 @@ -740,7 +740,7 @@ HsPar (and ParPat in patterns, HsParTy in types) is
 used as follows
 https://phabricator.haskell.org/rGHC499e43824bda967546ebf95ee33ec1f84a114a7c

    * ParPat and HsParTy are pretty printed as '( .. )' regardless of
 whether or
 -    not they are strictly necssary. This should be addressed when #13238
 is
 +    not they are strictly necessary. This should be addressed when #13238
 is

      completed, to be treated the same as HsPar.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14166>
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