[miniflare] fix: reject Miniflare#ready promise if dispose()ed while waiting

[mrbbot]

Fixes #4363.

What this PR solves / how to test:

This PR ensures Miniflare#ready is rejected if Miniflare#dispose() is called while waiting on the ready promise.

Author has addressed the following:

• Tests
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• Changeset (Changeset guidelines)
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• Associated docs
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[changeset-bot]

🦋 Changeset detected

Latest commit: 4e64a9a

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

This PR includes changesets to release 3 packages

Name	Type
miniflare	Patch
@cloudflare/pages-shared	Patch
wrangler	Patch

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[github-actions]

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

npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/6797238927/npm-package-wrangler-4397

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

npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/prs/6797238927/npm-package-wrangler-4397

Or you can use npx with this latest build directly:

npx https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/6797238927/npm-package-wrangler-4397 dev path/to/script.js

Additional artifacts:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/6797238927/npm-package-miniflare-4397

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/6797238927/npm-package-cloudflare-pages-shared-4397

Note that these links will no longer work once the GitHub Actions artifact expires.

---

wrangler@3.15.0 includes the following runtime dependencies:

Package	Constraint	Resolved
miniflare	workspace:*	3.20231025.1
workerd	1.20231030.0	1.20231030.0
workerd --version	1.20231030.0	2023-10-30

|

Please ensure constraints are pinned, and miniflare/workerd minor versions match.

[codecov]

Codecov Report

Merging #4397 (4e64a9a) into main (35be459) will increase coverage by 0.03%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #4397      +/-   ##
==========================================
+ Coverage   75.28%   75.31%   +0.03%     
==========================================
  Files         223      223              
  Lines       12357    12357              
  Branches     3198     3198              
==========================================
+ Hits         9303     9307       +4     
+ Misses       3054     3050       -4     

see 3 files with indirect coverage changes