build: add workaround for "pyinstaller with new setuptools" issue

Traceback (most recent call last):
  File "site-packages\PyInstaller\loader\rthooks\pyi_rth_pkgres.py", line 13, in <module>
  File "c:\python3\lib\site-packages\PyInstaller\loader\pyimod03_importers.py", line 623, in exec_module
  File "site-packages\pkg_resources\__init__.py", line 86, in <module>
ModuleNotFoundError: No module named 'pkg_resources.py2_warn'
[7048] Failed to execute script pyi_rth_pkgres

contrib/build-wine/deterministic.spec

@@ -16,6 +16,7 @@ home = 'C:\\electrum\\'
 
 # see https://github.com/pyinstaller/pyinstaller/issues/2005
 hiddenimports = []
+hiddenimports += collect_submodules('pkg_resources')  # workaround for https://github.com/pypa/setuptools/issues/1963
 hiddenimports += collect_submodules('trezorlib')
 hiddenimports += collect_submodules('safetlib')
 hiddenimports += collect_submodules('btchip')

contrib/osx/osx.spec

@@ -59,6 +59,7 @@ block_cipher = None
 
 # see https://github.com/pyinstaller/pyinstaller/issues/2005
 hiddenimports = []
+hiddenimports += collect_submodules('pkg_resources')  # workaround for https://github.com/pypa/setuptools/issues/1963
 hiddenimports += collect_submodules('trezorlib')
 hiddenimports += collect_submodules('safetlib')
 hiddenimports += collect_submodules('btchip')