fix: pages dev process exit when proxied process exits

[Skye-31]

Currently, if the process pages dev is proxying exists or crashes, pages dev does not clean it up, and attempts to continue proxying requests to it, resulting in it throwing 502 errors. This fixes that behaviour to make wrangler exit with the code the child_process exits with.

Possibly actually fixes #1544

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: 055b82c69c49d5ecbb787dc9820dbf3f5ddf2aa9

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
wrangler	Patch

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[github-actions[bot]]

A wrangler prerelease is available for testing. You can install this latest build in your project with:

npm install --save-dev https://prerelease-registry.developers.workers.dev/runs/2817340913/npm-package-wrangler-1628

You can reference the automatically updated head of this PR with:

npm install --save-dev https://prerelease-registry.developers.workers.dev/prs/1628/npm-package-wrangler-1628

Or you can use npx with this latest build directly:

npx https://prerelease-registry.developers.workers.dev/runs/2817340913/npm-package-wrangler-1628 dev path/to/script.js

[codecov[bot]]

Codecov Report

Merging #1628 (055b82c) into main (9e632cd) will increase coverage by 0.07%. The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main    #1628      +/-   ##
==========================================
+ Coverage   82.00%   82.07%   +0.07%     
==========================================
  Files          89       89              
  Lines        5884     5880       -4     
  Branches     1509     1510       +1     
==========================================
+ Hits         4825     4826       +1     
+ Misses       1059     1054       -5     

Impacted Files	Coverage Δ
packages/wrangler/src/pages/dev.tsx	24.64% <0.00%> (+0.67%)	:arrow_up:
...ackages/wrangler/src/__tests__/helpers/mock-bin.ts	100.00% <0.00%> (+5.26%)	:arrow_up: