Fixed the issue cannot create a SharedArrayBuffer

[goutamdh]

Fixes #2094

Changes:
Set Cross-Origin-Embedder-Policy and Cross-Origin-Opener-Policy headers This commit adds security headers to the server response to enable cross-origin isolation for shared memory operations in the p5.js editor.
I have verified that this pull request:

• has no linting errors (npm run lint)
• has no test errors (npm run test)
• is from a uniquely-named feature branch and is up to date with the develop branch.
• is descriptively named and links to an issue number, i.e. Fixes #123

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[raclim]

Thanks for your work on this! After testing this, I don't think what's here is the complete solution yet since the issue seems to still persist on my end! I don't exactly know what the right resolution looks like myself, but I feel like what's here is probably going in that vein. Since we have quite a few PRs open at the moment I'm going to close this one for now. I'm sorry that we couldn't get this one in, but please feel free to reopen this with any updates or check out our other issues!