exec groups: remove outdated --experimental_* documentation.
@@ -11,12 +11,6 @@ Each execution group has its own [toolchain](toolchains.md) dependencies and
performs its own [toolchain resolution](toolchains.md#toolchain-resolution).
## Current status
-To use Starlark rules that create execution groups, set
-`--experimental_exec_groups=true` on your command line or in a .bazelrc:
-
-```shell
-$ bazel build //target/with/exec/group --experimental_exec_groups
-```
## Background
