Update zig.gitignore to include .zig-cache dir

[melhindi]

Pull Request

Thank you for contributing to @toptal/gitignore and https://www.gitignore.io.

New or update

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New

• Template - New .gitignore template
• Composition - Template made from smaller templates
• Inheritance - Template similar to an existing template
• Patch - Template extending functionality of existing template

Update

• Template - Update existing .gitignore template

Details

Zig 0.13.0 compiler uses .zig-cache/ (with dot) instead of zig-cache, see https://ziglang.org/download/0.13.0/release-notes.html#codezig-cachecode-renamed-to-codezig-cachecode
We should leave the old zig-cache in the template for people using older versions of the zig compiler.