✨ Set the sha256 for slsa-verifier's v0.0.1

[laurentsimon]

This sets the expected sha256 of the v0.0.1 slsa-verifier released binary.

How to LGTM this PR (I'll work on a proper doc for this in #112):

1. Download the binary and provenance from https://github.com/slsa-framework/slsa-verifier/releases/tag/v0.0.1
2. Clone the slsa-verifier repo, compile and verify the provenance:

$ git clone git@github.com:slsa-framework/slsa-verifier.git
$ cd slsa-verifier
$ (Optional: git checkout tags/v1.0.0)
$ go run . -artifact-path slsa-verifier-linux-amd64 -provenance slsa-verifier-linux-amd64.intoto.jsonl -source github.com/slsa-framework/slsa-verifier -tag v0.0.1

3. Get the hash.
   Either:

cat slsa-verifier-linux-amd64.intoto.jsonl | jq -r '.payload' | base64 -d | jq -r '.subject[0].digest.sha256'

or

sha256sum slsa-verifier-linux-amd64

The output hash should be the hash I'm updating to in this PR. If they match, LGTM. If they don't, someone tampered with the released binary and don't LGTM

[asraa]

Confirmed hash!

asraa@asraa1:~/git/slsa-verifier$ go run . -artifact-path ~/Downloads/slsa-verifier-linux-amd64 -provenance ~/Downloads/slsa-verifier-linux-amd64.intoto.jsonl -source github.com/slsa-framework/slsa-verifier -tag v0.0.1
Verified against tlog entry 2461359
verified SLSA provenance produced at 
 {
	"caller": "slsa-framework/slsa-verifier",
	"commit": "f9e31da2a547a0c7093085a503c08a77167d5fea",
	"job_workflow_ref": "/slsa-framework/slsa-github-generator/.github/workflows/builder_go_slsa3.yml@refs/tags/v0.0.1",
	"trigger": "push",
	"issuer": "https://token.actions.githubusercontent.com"
}
successfully verified SLSA provenance
asraa@asraa1:~/git/slsa-verifier$ sha256sum ~/Downloads/slsa-verifier-linux-amd64
60c91c9d5b9a059e37ac46da316f20c81da335b5d00e1f74d03dd50f819694bd  /home/asraa/Downloads/slsa-verifier-linux-amd64