Use PyInstaller version 3.4

The newest version, 3.5, seems to have an issue
related to out test, which sadly is making the test
to fail.

Until this is not figured out, let's use 3.4
to avoid other patches to be merged.

Change-Id: I71e8aa616dff37b6c5b2552711140c0c0bf10d21
Reviewed-by: Christian Tismer <tismer@stackless.com>

coin_test_instructions.py

@@ -67,7 +67,8 @@ def call_testrunner(python_ver, buildnro):
     _pExe, _env, env_pip, env_python = get_qtci_virtualEnv(python_ver, CI_HOST_OS, CI_HOST_ARCH, CI_TARGET_ARCH)
     rmtree(_env, True)
     run_instruction(["virtualenv", "-p", _pExe,  _env], "Failed to create virtualenv")
-    install_pip_dependencies(env_pip, ["pip", "numpy", "PyOpenGL", "setuptools", "six", "pyinstaller"])
+    # Keeping PyInstaller 3.4, because 3.5 seems to have broken our test
+    install_pip_dependencies(env_pip, ["pip", "numpy", "PyOpenGL", "setuptools", "six", "pyinstaller==3.4"])
     install_pip_wheel_package(env_pip)
     cmd = [env_python, "testrunner.py", "test",
                   "--blacklist", "build_history/blacklist.txt",