Repository: electron/electron
Pull request: fix: deprecate ELECTRON_SKIP_BINARY_DOWNLOAD env

#### Description of Change
follow up to #50359
removes the `ELECTRON_SKIP_BINARY_DOWNLOAD` env from `install.js` as it is redundant
due to the post install script being dropped as of electron v42
(the ENVs sole purpose was to stop the postinstall script from triggering, however it is gone now, so the env is redundant)
and also adds mention of the env to the breaking changes doc
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#### Checklist
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- [x] PR description included
- [x] I have built and tested this PR
- [ ] `npm test` passes
- [ ] tests are [changed or added](https://github.com/electron/electron/blob/main/docs/development/testing.md)
- [ ] relevant API documentation, tutorials, and examples are updated and follow the [documentation style guide](https://github.com/electron/electron/blob/main/docs/development/style-guide.md)
- [x] [PR release notes](https://github.com/electron/clerk/blob/main/README.md) describe the change in a way relevant to app developers, and are [capitalized, punctuated, and past tense](https://github.com/electron/clerk/blob/main/README.md#examples).

#### Release Notes

Notes: Removed support for the ELECTRON_SKIP_BINARY_DOWNLOAD environment variable.

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Changed files:
filename: docs/breaking-changes.md
patch: @@ -98,6 +98,9 @@ npm install electron --save-dev
 ELECTRON_INSTALL_PLATFORM=mas npx electron . --no
 ```
 
+This also means the `ELECTRON_SKIP_BINARY_DOWNLOAD` environment variable is no
+longer supported, as its primary purpose was to prevent the `postinstall` script from running.
+
 ### Removed: `quotas` object from `Session.clearStorageData(options)`
 
 When calling `Session.clearStorageData(options)`, the `options.quotas` object is no longer supported because it has been

filename: docs/tutorial/installation.md
patch: @@ -25,16 +25,6 @@ included in the `electron` package:
 npx install-electron --no
 ```
 
-If you want to install your project's dependencies but don't need to use
-Electron functionality, you can set the `ELECTRON_SKIP_BINARY_DOWNLOAD` environment
-variable to prevent the binary from being downloaded. For instance, this feature can
-be useful in continuous integration environments when running unit tests that mock
-out the `electron` module.
-
-```sh
-ELECTRON_SKIP_BINARY_DOWNLOAD=1 npm install
-```
-
 ## Running Electron ad-hoc
 
 If you're in a pinch and would prefer to not use `npm install` in your local

filename: npm/install.js
patch: @@ -11,10 +11,6 @@ const path = require('path');
 
 const { version } = require('./package');
 
-if (process.env.ELECTRON_SKIP_BINARY_DOWNLOAD) {
-  process.exit(0);
-}
-
 const platformPath = getPlatformPath();
 
 if (isInstalled()) {