Windows builds panic due to a lack of support for system-level CA pool

[daniel-007]

zed version: zed 0.1.2
system: window 10 64
use command "zed schema read", there is error info :

panic: crypto/x509: system root pool is not available on Windows
goroutine 1 [running]:
github.com/authzed/grpcutil.WithSystemCerts(0x40)
        /Users/runner/go/pkg/mod/github.com/authzed/grpcutil@v0.0.0-20210913124023-cad23ae5a9e8/dial_opts.go:28 +0x49
main.dialOptsFromFlags(0xacba20, {0xc00048e000, 0x10})
        cmd/zed/main.go:37 +0x40a
main.schemaReadCmdFunc(0x134a6a0, {0x13bb5f8, 0x0, 0x0})
        cmd/zed/schema.go:69 +0x245
github.com/spf13/cobra.(*Command).execute(0x134a6a0, {0x13bb5f8, 0x0, 0x0})
        /Users/runner/go/pkg/mod/github.com/spf13/cobra@v1.2.1/command.go:856 +0x60e
github.com/spf13/cobra.(*Command).ExecuteC(0xc0003ecf00)
        /Users/runner/go/pkg/mod/github.com/spf13/cobra@v1.2.1/command.go:974 +0x3bc
github.com/spf13/cobra.(*Command).Execute(...)
        /Users/runner/go/pkg/mod/github.com/spf13/cobra@v1.2.1/command.go:902
main.main()
        cmd/zed/main.go:93 +0x459

[jzelinskie]

This certainly also affects SpiceDB.
Here's the upstream Go issue: golang/go#16736