Changed default Project Root when build.zig not found

[coffeebe4code]

Zig does not need a project root, but when viewing the std library, there is no build.zig. The current directory is fine for these purposes. zls remains quick on my linux machine.

Addresses this issue

[hsanson]

There are linter issues that need fixing:

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Running custom linting rules
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Custom warnings/errors follow:

ale_linters/zig/zls.vim:10 Trailing whitespace
ale_linters/zig/zls.vim:11 Trailing whitespace
./ale_linters/zig/zls.vim:11 Line continuation should match previous indentation
./ale_linters/zig/zls.vim:11 Indentation should be 4 spaces
./ale_linters/zig/zls.vim:13 Indentation should be 4 spaces