fix(fetch) clean declare structs

[cirospaciari]

What does this PR do?

• Documentation or TypeScript types (it's okay to leave the rest blank in this case)
• Code changes

How did you verify your code works?

Run #3862 test on release build with Bun.gc(true) before fetching

Fix: #3862

[github-actions]

❌ @cirospaciari 5 files with test failures on bun-darwin-aarch64:

• test/bundler/bundler_browser.test.ts
• test/js/bun/spawn/spawn-streaming-stdin.test.ts
• test/js/bun/spawn/spawn.test.ts
• test/js/bun/test/test-test.test.ts
• test/js/node/stubs.test.js

View test output

^{#0823e4c99a5d282acaa2a27018b5d46dd279fb2f}

[github-actions]

❌ @cirospaciari 3 files with test failures on linux-x64:

• test/bundler/bundler_browser.test.ts
• test/js/node/stubs.test.js
• test/js/third_party/prisma/prisma.test.ts

View test output

^{#0823e4c99a5d282acaa2a27018b5d46dd279fb2f}

[github-actions]

❌ @cirospaciari 2 files with test failures on linux-x64-baseline:

• test/bundler/bundler_browser.test.ts
• test/js/node/stubs.test.js

View test output

^{#0823e4c99a5d282acaa2a27018b5d46dd279fb2f}

[github-actions]

❌ @cirospaciari 6 files with test failures on bun-darwin-x64-baseline:

• test/bundler/bundler_browser.test.ts
• test/js/bun/spawn/spawn-streaming-stdin.test.ts
• test/js/bun/sqlite/sqlite.test.js
• test/js/node/stubs.test.js
• test/js/third_party/webpack/webpack.test.ts
• test/js/web/timers/setTimeout.test.js

View test output

^{#0823e4c99a5d282acaa2a27018b5d46dd279fb2f}

[Jarred-Sumner]

Very strange that this fixes anything at all