Launcher sets default upgrader policy

[EduardGomezEscandell]

This pull request depends on #217

Ubuntu desktop proposes upgrades according to a certain policy:

$ cat /etc/update-manager/release-upgrades
# Default behavior for the release upgrader.

[DEFAULT]
# Default prompting and upgrade behavior, valid options:
#
#  never  - Never check for, or allow upgrading to, a new release.
#  normal - Check to see if a new release is available.  If more than one new
#           release is found, the release upgrader will attempt to upgrade to
#           the supported release that immediately succeeds the
#           currently-running release.
#  lts    - Check to see if a new LTS release is available.  The upgrader
#           will attempt to upgrade to the first LTS release available after
#           the currently-running one.  Note that if this option is used and
#           the currently-running release is not itself an LTS release the
#           upgrader will assume prompt was meant to be normal.
Prompt=lts

There are different releases of Ubuntu WSL on the Microsoft store. These can be classified in three categories. Currently, the policy is always lts by default. This PR changes the default upgrader policy to:

Category	Releases in store	Desired default policy
Preview	Ubuntu (Preview)	normal
Latest LTS	Ubuntu	lts
Numbered	Ubuntu 18.04.5 LTS Ubuntu 20.04.4 LTS Ubuntu 22.04 LTS	never

[github-actions]

⚠️ Please check out carefully the isses found by clang-tidy in the new code ⚠️
⚠️ clang-format found formatting issues in the code submitted.:warning:
Make sure to run clang-format and update this pull request.
(1/1)

[github-actions]

⚠️ Please check out carefully the isses found by clang-tidy in the new code ⚠️
⚠️ clang-format found formatting issues in the code submitted.:warning:
Make sure to run clang-format and update this pull request.
(1/1)

[github-actions]

⚠️ Please check out carefully the isses found by clang-tidy in the new code ⚠️
⚠️ clang-format found formatting issues in the code submitted.:warning:
Make sure to run clang-format and update this pull request.
(1/2)

[github-actions]

⚠️ readability-simplify-boolean-expr ⚠️
redundant boolean literal in conditional return statement

Suggested change

	if (int cmdResult = _wsystem(shutdownCmd.c_str()); cmdResult != 0) {
	return cmdResult == 0;

[EduardGomezEscandell]

Closing in favour of refactored #226