[Submodule] Use https over git protocol

[ewalk153]

Description of the change

https is the preferred protocol for cloning repos. This switches the test262 reference to the https protocol.

Why am I making this change?

Cloning the submodule for test262 was failing for me.

Test instructions:

git submodule sync
git submodule update

Previously, I was hitting this security error:

➜  javy git:(add-crypto-hmac-256) ✗ git submodule update
Cloning into '/Users/a_user_name/src/github.com/bytecodealliance/javy/crates/javy/test262'...
git@github.com: Permission denied (publickey).
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.
fatal: clone of 'git@github.com:tc39/test262.git' into submodule path '/Users/a_user_name/src/github.com/bytecodealliance/javy/crates/javy/test262' failed
Failed to clone 'crates/javy/test262'. Retry scheduled
Cloning into '/Users/a_user_name/src/github.com/bytecodealliance/javy/crates/javy/test262'...
git@github.com: Permission denied (publickey).
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.
fatal: clone of 'git@github.com:tc39/test262.git' into submodule path '/Users/a_user_name/src/github.com/bytecodealliance/javy/crates/javy/test262' failed
Failed to clone 'crates/javy/test262' a second time, aborting

Checklist

• [ ] I've updated the relevant CHANGELOG files if necessary. Changes to javy-cli and javy-core do not require updating CHANGELOG files.
• [ ] I've updated the relevant crate versions if necessary. Versioning policy for library crates
• [ ] I've updated documentation including crate documentation if necessary.