Upgrade minimum go to 1.17

[fangn2]

Issue #, if available:

Description of changes:
Upgrade minimum go to 1.17 to unblock dependency golang.org/x/net update PR #497 which requires go 1.17+.
Currently it's failing with error:

go build -o snapshot-example
--
  | go: downloading golang.org/x/sys v0.8.0
  | # golang.org/x/sys/unix
  | ../../../../../../../go/pkg/mod/golang.org/x/[email protected]/unix/syscall.go:83:16: undefined: unsafe.Slice
  | ../../../../../../../go/pkg/mod/golang.org/x/[email protected]/unix/syscall_linux.go:1018:20: undefined: unsafe.Slice
  | ../../../../../../../go/pkg/mod/golang.org/x/[email protected]/unix/syscall_linux.go:2297:9: undefined: unsafe.Slice
  | ../../../../../../../go/pkg/mod/golang.org/x/[email protected]/unix/syscall_unix.go:118:7: undefined: unsafe.Slice
  | ../../../../../../../go/pkg/mod/golang.org/x/[email protected]/unix/sysvshm_unix.go:33:7: undefined: unsafe.Slice
  | note: module requires Go 1.17
  | make: *** [Makefile:73: snapshot-example] Error 2
  | 🚨 Error: The command exited with status 2
  | user command error: exit status 2

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[swagatbora90]

LGTM. Good to merge provided CI steps are passing.

[fangn2]

Buildkite CI is failing on building Firecracker from tip of Firecracker's main branch which is not related to this change.
The CI has been failing for the same reason in the last 9 consecutive nightly builds.