Minor package description refactoring

This makes use of `common` blocks to reduce the duplication resulting
from three test-suite components sharing the very same settings.

Also, this declares all `LANGUAGE` pragmas we expect the compiler to
support so the cabal solver can honor this.

Author: hvr

cryptohash-sha512.cabal

@@ -1,4 +1,4 @@
-cabal-version:       2.0
+cabal-version:       2.2
 name:                cryptohash-sha512
 version:             0.11.103.0
 
@@ -45,7 +45,7 @@ a [clearly smaller footprint by almost 3 orders of magnitude](https://www.reddit
 
 }
 
-license:             BSD3
+license:             BSD-3-Clause
 license-file:        LICENSE
 copyright:           Vincent Hanquez, Herbert Valerio Riedel
 maintainer:          Herbert Valerio Riedel <hvr@gnu.org>
@@ -77,22 +77,28 @@ source-repository head
 
 library
   default-language:  Haskell2010
+  other-extensions:  BangPatterns
+                     CApiFFI
+                     CPP
+                     Trustworthy
+                     Unsafe
   build-depends:     base             >= 4.5   && < 5
                    , bytestring       >= 0.9.2 && < 0.13
 
   hs-source-dirs:    src
   exposed-modules:   Crypto.Hash.SHA512 Crypto.Hash.SHA512t Crypto.Hash.SHA384
   other-modules:     Crypto.Hash.SHA512.FFI Compat
-  ghc-options:       -Wall -fno-cse -O2
+  ghc-options:       -Wall -fno-warn-deprecations -fno-cse -O2
   cc-options:        -Wall
   include-dirs:      cbits
 
-test-suite test-sha512
+common test-defaults
   default-language:  Haskell2010
-  type:              exitcode-stdio-1.0
-  hs-source-dirs:    src-tests
-  main-is:           test-sha512.hs
+  other-extensions:  OverloadedStrings
   ghc-options:       -Wall -threaded
+
+  hs-source-dirs:    src-tests
+
   build-depends:     cryptohash-sha512
                    , base
                    , bytestring
@@ -103,40 +109,24 @@ test-suite test-sha512
                    , tasty-quickcheck  >= 0.10     && < 1
                    , tasty-hunit       >= 0.10     && < 0.11
 
+test-suite test-defaults
+  import:            test-defaults
+  type:              exitcode-stdio-1.0
+  main-is:           test-sha512.hs
+
 test-suite test-sha512t
-  default-language:  Haskell2010
+  import:            test-defaults
   type:              exitcode-stdio-1.0
-  hs-source-dirs:    src-tests
   main-is:           test-sha512t.hs
-  ghc-options:       -Wall -threaded
-  build-depends:     cryptohash-sha512
-                   , base
-                   , bytestring
-
-                   , base16-bytestring >= 1.0.1.0  && < 1.1
-                   , SHA               >= 1.6.4    && < 1.7
-                   , tasty             >= 1.4      && < 1.6
-                   , tasty-quickcheck  >= 0.10     && < 1
-                   , tasty-hunit       >= 0.10     && < 0.11
 
 test-suite test-sha384
-  default-language:  Haskell2010
+  import:            test-defaults
   type:              exitcode-stdio-1.0
-  hs-source-dirs:    src-tests
   main-is:           test-sha384.hs
-  ghc-options:       -Wall -threaded
-  build-depends:     cryptohash-sha512
-                   , base
-                   , bytestring
-
-                   , base16-bytestring >= 1.0.1.0  && < 1.1
-                   , SHA               >= 1.6.4    && < 1.7
-                   , tasty             >= 1.4      && < 1.6
-                   , tasty-quickcheck  >= 0.10     && < 1
-                   , tasty-hunit       >= 0.10     && < 0.11
 
 benchmark bench-sha512
   default-language:  Haskell2010
+  other-extensions:  BangPatterns
   type:              exitcode-stdio-1.0
   main-is:           bench-sha512.hs
   hs-source-dirs:    src-bench