chore: update toolchain

Update dependencies:
```
toolchain: v1.13.0-beta.0
```

Signed-off-by: Mateusz Urbanek <mateusz.urbanek@siderolabs.com>

Author: shanduur

Pkgfile

@@ -5,7 +5,7 @@
 format: v1alpha2
 
 vars:
-  TOOLCHAIN_IMAGE: ghcr.io/siderolabs/toolchain:v1.13.0-alpha.0-6-g5b44ff9
+  TOOLCHAIN_IMAGE: ghcr.io/siderolabs/toolchain:v1.13.0-beta.0
 
   # renovate: datasource=github-tags depName=argp-standalone/argp-standalone
   argp_standalone_version: 1.5.0