Update crypto.rs

[leonjia0112]

This is an example implementation of a hardcoded long string,
which rust-fmt won't be able to take the case of. Use format!()
to concentrate long two short string to create a long string,
instead of putting a single long string together.

[frozencemetery]

Please refer to how to write a git commit message. In particular, the subject of this commit isn't useful (I know that it updates crypto.rs from the files changed already...) and more importantly I have no idea why this change is being made.

[leonjia0112]

Please refer to how to write a git commit message. In particular, the subject of this commit isn't useful (I know that it updates crypto.rs from the files changed already...) and more importantly I have no idea why this change is being made.

I feel like the string is too long in here, which can be shortened a little bit. For such kind of thing, rustfmt won't take care of it. But I will update the commit message to make it a little more meaningful.

[leonjia0112]

Change addressed and test passed.
Ready for a review. @frozencemetery @mbestavros