Update example repositories to Pants 2.19

[huonw]

Now that 2.19.0 is released, we should update all the example- repos to use it, by adjusting their pants.toml to have pants_version = "2.19.0": https://github.com/pantsbuild?q=example&type=all&language=&sort=name

• [ ] https://github.com/pantsbuild/example-adhoc
• [ ] https://github.com/pantsbuild/example-codegen
• [ ] https://github.com/pantsbuild/example-django
• [ ] https://github.com/pantsbuild/example-docker
• [ ] https://github.com/pantsbuild/example-golang
• [ ] https://github.com/pantsbuild/example-javascript
• [ ] https://github.com/pantsbuild/example-jvm
• [ ] https://github.com/pantsbuild/example-kotlin
• [x] https://github.com/pantsbuild/example-python (https://github.com/pantsbuild/example-python/pull/133)
• [ ] https://github.com/pantsbuild/example-serverless
• [ ] https://github.com/pantsbuild/example-visibility

(NB. not https://github.com/pantsbuild/example-plugin)

Bonus points (repos that use pants but aren't examples):

• [ ] https://github.com/pantsbuild/scie-pants
• [ ] https://github.com/pantsbuild/setup

[kaos]

we should have a dependabot thing for this......... ;)

[huonw]

2.20 is out now, so closing this in favour of https://github.com/pantsbuild/pants/issues/20799.