[DO-1345] fixed windows packages (!16)

Reviewed-on: https://git.avroid.tech/Conan/conan_build/pulls/16
Co-authored-by: aleksandr.vodyanov <aleksandr.vodyanov@avroid.team>
Co-committed-by: aleksandr.vodyanov <aleksandr.vodyanov@avroid.team>

recipes/msys2/all/test_package/conanfile.py

@@ -0,0 +1,34 @@
+from conan import ConanFile
+from conan.tools.env import Environment
+from io import StringIO
+
+
+class TestPackageConan(ConanFile):
+    settings = "os", "arch"
+    generators = "VirtualBuildEnv"
+    test_type = "explicit"
+
+    def build_requirements(self):
+        self.tool_requires(self.tested_reference_str)
+
+    @property
+    def _secret_value(self):
+        return "SECRET_CONAN_PKG_VARIABLE"
+
+    def generate(self):
+        env = Environment()
+        env.define("PKG_CONFIG_PATH", self._secret_value)
+        envvars = env.vars(self)
+        envvars.save_script("conanbuildenv_pkg_config_path")
+
+    def build(self):
+        pass # nothing to do, skip hook warning
+
+    def test(self):
+        self.run('bash.exe -c ^"make --version^"')
+        self.run('bash.exe -c ^"! test -f /bin/link^"')
+        self.run('bash.exe -c ^"! test -f /usr/bin/link^"')
+
+        output = StringIO()
+        self.run('bash.exe -c "echo $PKG_CONFIG_PATH"', output)
+        assert self._secret_value in output.getvalue()