It is _very_ common to override the execution of `bazelisk`.

This means that using a `!reference` any time the `script` is
overridden to copy the run files.

Moving this to `before_script` negates that.

This makes the component include path consistent on 16.3/16.5+.

They changed the template structure from:

```
├── template.yml
├── README.md
├── .gitlab-ci.yml
├── unit/
│   └── template.yml
└── integration/
    └── template.yml
```

To:

```
├── README.md
├── .gitlab-ci.yml
└── templates/
    └── all-scans.yml
    └── secret-detection.yml
```

Unfortunately, symlinks are *not* supported so until we can drop support
for 16.3, we'll have to copy over changes.

BREAKING CHANGE: The component must be included via the `bazelisk` name.

The nameless include in `1.0.0-beta.1` is no longer supported.

```
include:
  - component: "${CI_SERVER_HOST}/ci/component/bazelisk@1.0.0-beta.1"
```

Add the `/bazelisk` named CI component:

```
include:
  - component: "${CI_SERVER_HOST}/ci/component/bazelisk/bazelisk@1.0.0-beta.2"
```

This is due to GitLab CI components being stabilised and the nameless component
support being removed.

Builds a `bazelisk` image for multiple architectures using `rules_oci`.

Provides a `template.yml` GitLab CI component.