Update descriptions

client/ghc-debug-client.cabal

 cabal-version:       3.0
 name:                ghc-debug-client
 version:             0.1.0.0
--- synopsis:
--- description:
+synopsis:            Useful functions for writing heap analysis tools which use
+                     ghc-debug.
+description:         Useful functions for writing heap analysis tools which use
+                     ghc-debug.
 homepage:            https://gitlab.haskell.org/ghc/ghc-debug
 license:             BSD-3-Clause
 license-file:        LICENSE

common/ghc-debug-common.cabal

 cabal-version:       3.0
 name:                ghc-debug-common
 version:             0.1.0.0
-synopsis:            A debugger for GHC
--- description:
+synopsis:            Connect to a socket created by ghc-debug-stub and analyse
+                     the heap of the debuggee program.
+description:         Connect to a socket created by ghc-debug-stub and analyse
+                     the heap of the debuggee program.
 homepage:            https://gitlab.haskell.org/ghc/ghc-debug
 license:             BSD-3-Clause
 license-file:        LICENSE

stub/ghc-debug-stub.cabal

 cabal-version:       2.4
 name:                ghc-debug-stub
 version:             0.1.0.0
--- synopsis:
--- description:
+synopsis:            Functions for instrumenting your application so the heap
+                     can be analysed with ghc-debug-common.
+description:         Functions for instrumenting your application so the heap can
+                     be analysed with ghc-debug-common.
 homepage:            https://gitlab.haskell.org/ghc/ghc-debug
 license:             BSD-3-Clause
 license-file:        LICENSE