Use Main.Version to put the versioning

[sixstone-qq]

Without this PR, the version has to be set manually before each git tag versioning which becomes outdated (see v0.2.0 on this changeset). In order to let our users known which tool version are using, there is a hkt version command.

In order to fix this, this PR puts versioning dynamically following this flow:

If injected Version is set, use it. If not, read it from runtime.debug.ReadBuildInfo, if not available, just put devel.

[sixstone-qq]

QA:
Using go install:

✦4 ❯ go install github.com/heetch/hkt@put-version
go: downloading github.com/heetch/hkt v0.5.1-0.20220407082758-2ae908d8392f

services/phasing/core on  master [$?] via GO v1.17.1 took 28s
✦4 ❯ hkt version
hkt version v0.5.1-0.20220407082758-2ae908d8392f

Using make build:

✦4 ❯ make build && ./hkt version
go build -ldflags="-X main.Version=v0.5.0-2-g427502f"
hkt version v0.5.0-2-g427502f