cabal.project: Fix/improve running of tests

Disable all tests by default (to make sure tests in git dependencies
are not built/run) and then enable tests for packages in this repository.

Users need to make sure that 'cabal.project.local' does not include
'tests:True'.

cabal.project

@@ -18,96 +18,48 @@ package cardano-config
 package cardano-node
   ghc-options: -Werror -Wall -Wredundant-constraints -Wincomplete-record-updates -Wincomplete-uni-patterns -Wpartial-fields
 
+-- ---------------------------------------------------------
+-- Disable all tests by default
 
-package ouroboros-consensus
-  tests: False
+tests: False
 
-package ouroboros-consensus-cardano
-  tests: False
+test-show-details: direct
 
-package ouroboros-consensus-byron
-  tests: False
+-- Then enable specific tests in this repo
 
-package ouroboros-consensus-shelley
-  tests: False
+package cardano-api
+  tests: True
 
-package bech32
-  tests: False
+package cardano-cli
+  tests: True
 
-package byron-spec-chain
-  tests: False
+package cardano-node
+  tests: True
 
+-- The following is needed because Nix is doing something crazy.
 package byron-spec-ledger
   tests: False
 
-package small-steps-test
-  tests: False
-
-package cardano-crypto
-  tests: False
-
-package cborg
-  tests: False
-
-package http-client
-  tests: False
-
-package goblins
-  tests: False
-
-package io-sim
-  tests: False
-
-package io-sim-classes
-  tests: False
-
-package shelley-spec-non-integral
-  tests: False
-
-package network-mux
-  tests: False
-
-package typed-protocols
-  tests: False
-
-package typed-protocols-examples
-  tests: False
-
-package cardano-prelude
-  tests: False
-
-package iohk-monitoring
-  tests: False
-
-package cardano-binary
+package ouroboros-consensus
   tests: False
 
-package cardano-sl-x509
+package ouroboros-consensus-cardano
   tests: False
 
-package cardano-crypto-class
+package ouroboros-consensus-cardano
   tests: False
 
-package cardano-crypto-wrapper
+package ouroboros-network
   tests: False
 
 package ouroboros-network-framework
   tests: False
 
-package lobemo-backend-monitoring
-  tests: False
-
 package small-steps
   tests: False
 
-package ouroboros-network
-  tests: False
-
-package shelley-spec-ledger
-  tests: False
+-- ---------------------------------------------------------
 
-package cardano-ledger
-  tests: False
 
 -- The two following one-liners will restore / cut off the remainder of this file (for nix-shell users):
 -- git checkout HEAD "$(git rev-parse --show-toplevel)"/cabal.project