App: Force plugin server to use localhost

[ethanwharris]

What does this PR do?

Requires plugin server to use localhost

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📚 Documentation preview 📚: https://pytorch-lightning--18976.org.readthedocs.build/en/18976/

cc @Borda

[github-actions]

⚡ Required checks status: All passing 🟢

Groups summary

🟢 lightning_app: Tests workflow

Check ID	Status
app-pytest (macOS-11, lightning, 3.8, latest)	success	✅
app-pytest (macOS-11, lightning, 3.8, oldest)	success	✅
app-pytest (macOS-11, app, 3.9, latest)	success	✅
app-pytest (macOS-12, app, 3.11, latest)	success	✅
app-pytest (ubuntu-20.04, lightning, 3.8, latest)	success	✅
app-pytest (ubuntu-20.04, lightning, 3.8, oldest)	success	✅
app-pytest (ubuntu-20.04, app, 3.9, latest)	success	✅
app-pytest (ubuntu-22.04, app, 3.11, latest)	success	✅
app-pytest (windows-2022, lightning, 3.8, latest)	success	✅
app-pytest (windows-2022, lightning, 3.8, oldest)	success	✅
app-pytest (windows-2022, app, 3.8, latest)	success	✅
app-pytest (windows-2022, app, 3.11, latest)	success	✅

These checks are required after the changes to src/lightning/app/plugin/plugin.py, tests/tests_app/plugin/test_plugin.py.

🟢 lightning_app: Examples

Check ID	Status
app-examples (macOS-11, lightning, 3.9, latest)	success	✅
app-examples (macOS-11, lightning, 3.9, oldest)	success	✅
app-examples (macOS-11, app, 3.9, latest)	success	✅
app-examples (ubuntu-20.04, lightning, 3.9, latest)	success	✅
app-examples (ubuntu-20.04, lightning, 3.9, oldest)	success	✅
app-examples (ubuntu-20.04, app, 3.9, latest)	success	✅
app-examples (windows-2022, lightning, 3.9, latest)	success	✅
app-examples (windows-2022, lightning, 3.9, oldest)	success	✅
app-examples (windows-2022, app, 3.9, latest)	success	✅

These checks are required after the changes to src/lightning/app/plugin/plugin.py.

🟢 lightning_app: Docs

Check ID	Status
docs-make (app, doctest)	success	✅
docs-make (app, html)	success	✅

These checks are required after the changes to src/lightning/app/plugin/plugin.py.

🟢 mypy

Check ID	Status
mypy	success	✅

These checks are required after the changes to src/lightning/app/plugin/plugin.py.

🟢 install

Check ID	Status
install-pkg (ubuntu-22.04, app, 3.8)	success	✅
install-pkg (ubuntu-22.04, app, 3.11)	success	✅
install-pkg (ubuntu-22.04, fabric, 3.8)	success	✅
install-pkg (ubuntu-22.04, fabric, 3.11)	success	✅
install-pkg (ubuntu-22.04, pytorch, 3.8)	success	✅
install-pkg (ubuntu-22.04, pytorch, 3.11)	success	✅
install-pkg (ubuntu-22.04, lightning, 3.8)	success	✅
install-pkg (ubuntu-22.04, lightning, 3.11)	success	✅
install-pkg (ubuntu-22.04, notset, 3.8)	success	✅
install-pkg (ubuntu-22.04, notset, 3.11)	success	✅
install-pkg (macOS-12, app, 3.8)	success	✅
install-pkg (macOS-12, app, 3.11)	success	✅
install-pkg (macOS-12, fabric, 3.8)	success	✅
install-pkg (macOS-12, fabric, 3.11)	success	✅
install-pkg (macOS-12, pytorch, 3.8)	success	✅
install-pkg (macOS-12, pytorch, 3.11)	success	✅
install-pkg (macOS-12, lightning, 3.8)	success	✅
install-pkg (macOS-12, lightning, 3.11)	success	✅
install-pkg (macOS-12, notset, 3.8)	success	✅
install-pkg (macOS-12, notset, 3.11)	success	✅
install-pkg (windows-2022, app, 3.8)	success	✅
install-pkg (windows-2022, app, 3.11)	success	✅
install-pkg (windows-2022, fabric, 3.8)	success	✅
install-pkg (windows-2022, fabric, 3.11)	success	✅
install-pkg (windows-2022, pytorch, 3.8)	success	✅
install-pkg (windows-2022, pytorch, 3.11)	success	✅
install-pkg (windows-2022, lightning, 3.8)	success	✅
install-pkg (windows-2022, lightning, 3.11)	success	✅
install-pkg (windows-2022, notset, 3.8)	success	✅
install-pkg (windows-2022, notset, 3.11)	success	✅

These checks are required after the changes to src/lightning/app/plugin/plugin.py.

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Thank you for your contribution! 💜

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[tchaton]

LGTM !