Update bootstrap.sh

[angerman]

bootstrap should fail on die; and not contiune.

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[angerman]

Where do these windows failures come from, all of a sudden?

cd ..\cabal-install
..\cabal test unit-tests --show-details=streaming --test-option=--pattern=!FileMonitor --test-option=--hide-successes
Preprocessing library for cabal-install-2.1.0.0..
Building library for cabal-install-2.1.0.0..
Preprocessing test suite 'unit-tests' for cabal-install-2.1.0.0..
Building test suite 'unit-tests' for cabal-install-2.1.0.0..
Generating manual page dist\build\cabal/cabal.1 ...
Running 1 test suites...
Test suite unit-tests: RUNNING...
File modification time resolution calibration completed, maximum delay
observed: 15.628 ms. Will be using delay of 31.256 for test runs.
Unit Tests
  UnitTests.Distribution.Solver.Modular.Solver
    build-tool-depends
      choose exe after choosing its package - failure:                       FAIL
        tests\UnitTests\Distribution\Solver\Modular\DSL\TestCaseUtils.hs:214:
        Unexpected error:
        Could not resolve dependencies:
        [__0] trying: A-1.0.0 (user goal)
        [__1] trying: A:+flagA
        [__2] next goal: A:B:exe.B (dependency of A)
        [__2] rejecting: A:B:exe.B-1.0.0 (does not contain executable exe2, which is required by A +flagA)
        After searching the rest of the dependency tree exhaustively, these were the goals I've had most trouble fulfilling: A, A:flagA, A:B:exe.B, unknown

[23Skidoo]

Let's try reverting #5012.

[23Skidoo]

Merged, thanks!