Update actions/checkout action to v2

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	major	v1 -> v2

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Release Notes

actions/checkout

### [`v2`](https://togithub.com/actions/checkout/blob/master/CHANGELOG.md#v231) [Compare Source](https://togithub.com/actions/checkout/compare/v1...v2) - [Fix default branch resolution for .wiki and when using SSH](https://togithub.com/actions/checkout/pull/284)

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Configuration

📅 Schedule: "before 3am on the first day of the month" in timezone Europe/Stockholm.

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻️ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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• [ ] If you want to rebase/retry this PR, check this box.

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[codecov[bot]]

Codecov Report

Merging #209 (7260269) into master (5698c05) will not change coverage. The diff coverage is n/a.

:exclamation: Current head 7260269 differs from pull request most recent head c2e8548. Consider uploading reports for the commit c2e8548 to get more accurate results

@@           Coverage Diff           @@
##           master     #209   +/-   ##
=======================================
  Coverage   30.33%   30.33%           
=======================================
  Files          29       29           
  Lines         356      356           
  Branches       18       18           
=======================================
  Hits          108      108           
  Misses        248      248           

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Continue to review full report at Codecov.

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[github-actions[bot]]

Size Change: 0 B

Total Size: 592 kB

ℹ️ View Unchanged

| Filename | Size | Change | | :--- | :---: | :---: | | `client/dist/css/app.css` | 121 kB | 0 B | | `client/dist/css/chunk-e1b55505.css` | 37 B | 0 B | | `client/dist/css/chunk-5c4469b5.css` | 37 B | 0 B | | `client/dist/css/chunk-bff537b0.css` | 308 B | 0 B | | `client/dist/css/chunk-2bb63e37.css` | 66 B | 0 B | | `client/dist/css/chunk-773ad777.css` | 137 B | 0 B | | `client/dist/css/chunk-a847f253.css` | 119 B | 0 B | | `client/dist/js/app.js` | 5.5 kB | 0 B | | `client/dist/js/chunk-788bce6a.js` | 1.45 kB | 0 B | | `client/dist/js/chunk-516794e1.js` | 1.01 kB | 0 B | | `client/dist/js/chunk-515340d3.js` | 822 B | 0 B | | `client/dist/js/chunk-d58d638d.js` | 1.14 kB | 0 B | | `client/dist/js/chunk-9b35c7ac.js` | 1.2 kB | 0 B | | `client/dist/js/chunk-6f8f5519.js` | 300 B | 0 B | | `client/dist/js/chunk-de6018f1.js` | 300 B | 0 B | | `client/dist/js/chunk-6a278c5b.js` | 296 B | 0 B | | `client/dist/js/chunk-9c408f1d.js` | 690 B | 0 B | | `client/dist/js/chunk-7ef8bfd1.js` | 895 B | 0 B | | `client/dist/js/chunk-8f35bf28.js` | 1.06 kB | 0 B | | `client/dist/js/chunk-62b87ffb.js` | 1.6 kB | 0 B | | `client/dist/js/chunk-d1035716.js` | 800 B | 0 B | | `client/dist/js/chunk-92fec854.js` | 870 B | 0 B | | `client/dist/js/chunk-ab87b272.js` | 844 B | 0 B | | `client/dist/js/chunk-9efae2f7.js` | 1.28 kB | 0 B | | `client/dist/js/chunk-faf1741d.js` | 1.37 kB | 0 B | | `client/dist/js/chunk-7b8736de.js` | 1.8 kB | 0 B | | `client/dist/js/chunk-23b5bb22.js` | 324 B | 0 B | | `client/dist/js/chunk-vendors.js` | 439 kB | 0 B | | `server/dist/index.js` | 295 B | 0 B | | `server/dist/src/app.js` | 586 B | 0 B | | `server/dist/src/app/customer/customer-model.js` | 291 B | 0 B | | `server/dist/src/app/customer/customer-route.js` | 506 B | 0 B | | `server/dist/src/app/order/order-model.js` | 316 B | 0 B | | `server/dist/src/app/order/order-route.js` | 532 B | 0 B | | `server/dist/src/app/product/product-model.js` | 276 B | 0 B | | `server/dist/src/app/product/product-route.js` | 505 B | 0 B | | `server/dist/src/build/build-controller.js` | 691 B | 0 B | | `server/dist/src/build/build-route.js` | 337 B | 0 B | | `server/dist/src/entities/entities-controller.js` | 421 B | 0 B | | `server/dist/src/entities/entities-route.js` | 328 B | 0 B | | `server/dist/src/models.js` | 504 B | 0 B | | `server/dist/src/routes.js` | 309 B | 0 B | | `server/dist/src/utils/file.js` | 361 B | 0 B | | `server/dist/src/utils/index.js` | 331 B | 0 B | | `server/dist/src/utils/paths.js` | 290 B | 0 B | | `server/dist/src/utils/templating.js` | 659 B | 0 B | | `server/dist/tests/app.test.js` | 381 B | 0 B |

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