erlang_ls: Look for lib includes in extra_deps

[the-mikedavis]

Proposed Changes

This fixes ErlangLS include lookups for include_lib attributes like

-include_lib("khepri/lib/include.hrl").

when running erlang_ls and building with Bazel.

khepri ends up in the extra_deps directory as a symlink after running bazel run //tools:symlink_deps_for_erlang_ls, so this change picks up that khepri directory as a lib for include_libs.

This fixes some spurious diagnostics from erlang_ls running on #7206.

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