py-pyproj: update to 3.7.0, add py313 subport, remove py38 subport

[markmentovai]

Description

py38-pyproj only had one dependency, py38-owslib, which is removed here.

Type(s)

• bugfix
• enhancement
• security fix

Tested on

macOS 15.1 24B83 arm64
Xcode 16.1 16B40

Verification

Have you

• followed our Commit Message Guidelines?
• squashed and minimized your commits?
• checked that there aren't other open pull requests for the same change?
• referenced existing tickets on Trac with full URL in commit message?
• checked your Portfile with port lint --nitpick?
• tried existing tests with sudo port test?
• tried a full install with sudo port -vst install?
• tested basic functionality of all binary files?
• checked that the Portfile's most important variants haven't been broken?

[macportsbot]

Notifying maintainers:
@petrrr for port py-owslib.
@stromnov for port py-pyproj.