Support minimum supported bazel version check from bazelisk's .bazelversion

Gerrit Code Review project is optionally supporting [Bazelisk](https://github.com/bazelbuild/bazelisk), by providing `.bazelversion` file. In the same time, we are checking the minimum supported Bazel version in `WORKSPACE` file by using bazel_skylib's `versions.check()` function (in case the build is invoked with Bazel and not with Bazelisk command), e.g.:

```
http_archive(
name = "bazel_skylib",
sha256 = "2ea8a5ed2b448baf4a6855d3ce049c4c452a6470b1efd1504fdb7c1c134d220a",
strip_prefix = "bazel-skylib-0.8.0",
urls = ["https://github.com/bazelbuild/bazel-skylib/archive/0.8.0.tar.gz"],
)

load("@bazel_skylib//lib:versions.bzl", "versions")

versions.check(minimum_bazel_version = "0.29.0")
```

However, this is disadvantageously, to maintain Bazel versions in two different places, and upgrade them in two places, when Bazel version is bumped, like it was done in this CL: [1]:

1. `.bazelversion`
2. `WORKSPACE`

What we need is a supported built-in way to check minimum supported Bazel version check from `.bazelversion`, e.g.:

```
bazel_version_check_from_bazelversion_file()
```

with the outcome, that the Build would break, if Bazel version is less than 0.29.

Bonus point, would be to not invoke anything, but just add a line in `.bazelrc` file, e.g.:

```
build --bazel_version_check_from_bazelversion_file
```

Even a bigger bonus point, when this check performed automatically, without saying anything (neither in `WORKSPACE` nor in `.bazelrc` files). So, if there is `.bazelversion` file with content `1.0.0`, and I am invoking the build with `bazel` version 0.0.1, then the build should just fail.

[1] https://gerrit-review.googlesource.com/c/gerrit/+/232533

Start by reading the .bazelversion file and the versions.check() call in WORKSPACE, then compare how the existing Bazelisk setup is used. Review the proposed .bazelrc option and automatic-check alternatives in the issue. Done means the minimum supported version has one source of truth and a build using an older version fails.

Written by the indexing model from the issue text.