Hinetpy

Add the updated solution for the "ssl.SSLError: [SSL: DH_KEY_TOO_SMALL] dh key too small" error

Minor changes to refactor some internal functions.

- Support more newly added networks
- Drop support for Python 3.7
- Remove the hacking solution for SSL connection issue so it works well with urllib3 v2.x

Fix bugs in `Client.get_event_waveform`

- Fix the incorrect maximum allowed time span for F-net (65)
- `get_selected_stations` now returns a list of stations with station metadata
information (36)
- Refactor the `_channel2pz()` and `_write_pz()` functions to `Channel.write_sacpz()`
- Refactor the `_get_channels` function to `win32.read_ctable()`
- The `win32.extrac_sacpz` function now supports parallel data processing
- The `with_pz` parameter in `win32.extract_sac()` is renamed to `with_sacpz`
- The `win32.extrac_pz()` function is renamed to `win32.extract_sacpz()`
- Move the function `Client.check_cmd_exists()` to `utils.check_cmd_exists()`
- Move the function `Client.check_package_release()` to `utils.check_package_release()`
- Fix the "ssl.SSLError: [SSL: DH_KEY_TOO_SMALL] dh key too small" error

This is a patch release of HinetPy v0.6.x series.

One bug is fixed:

- The `stations` parameter of `Client.select_stations()` now can accept a string (for a single station) or a list of strings (multiple stations).