Encourage setting PHP version explicitly

[rmccue]

See humanmade/altis-core#590 - we should encourage users to explicitly set the PHP platform version.

[rmccue]

It may be worth us changing the other config change notes to use the composer config command too, since it's harder to do that wrong

[kadamwhite]

I don't think this clarifies the order of operations in a way that would have prevented my issue. If I'm understanding correctly, my mistake was that I upgraded too far while trying to prepare for PHP8, and the text that has been added here doesn't give me any direction that I would have understood. What about something like,

If you are deploying to a live environment that has not yet been upgraded to your target PHP version, the steps above may have resulted in incompatible dependencies for the current PHP version. Set the PHP version target back to the current server target and re-run update Altis with all dependencies to pin any sub dependencies at PHP 7.4-compatible versions.

If there's a different order of operations, for example if we should only deploy Altis 12 alongside a full upgrade to PHP 8, I think that would be good to call out.

[rmccue]

The section entitled "Switch Off Composer's Platform Check" should cover this already?

[roborourke]

@rmccue I'm not sure the issue was to do with the platform check from Composer exactly but an uninstallable set of dependencies for the current PHP version based on the composer.lock file.

[hm-backport]

The backport to v12-branch failed:

Commits ["3fc68c23ce94fbe6d4bfcee7e591a1341cdc312e","06dd76859bc399d39aad460633b69cbaa6e8f94d"] could not be cherry-picked on top of v12-branch

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub.
git fetch
# Create new working tree.
git worktree add .worktrees/backport v12-branch
# Navigate to the new directory.
cd .worktrees/backport
# Cherry-pick all the commits of this pull request and resolve the likely conflicts.
git cherry-pick 3fc68c23ce94fbe6d4bfcee7e591a1341cdc312e 06dd76859bc399d39aad460633b69cbaa6e8f94d
# Create a new branch with these backported commits.
git checkout -b backport-430-to-v12-branch
# Push it to GitHub.
git push --set-upstream origin backport-430-to-v12-branch
# Go back to the original working tree.
cd ../..
# Delete the working tree.
git worktree remove .worktrees/backport

Then, create a pull request where the base branch is v12-branch and the compare/head branch is backport-430-to-v12-branch.

[hm-backport]

The backport to v13-branch failed:

Commits ["3fc68c23ce94fbe6d4bfcee7e591a1341cdc312e","06dd76859bc399d39aad460633b69cbaa6e8f94d"] could not be cherry-picked on top of v13-branch

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub.
git fetch
# Create new working tree.
git worktree add .worktrees/backport v13-branch
# Navigate to the new directory.
cd .worktrees/backport
# Cherry-pick all the commits of this pull request and resolve the likely conflicts.
git cherry-pick 3fc68c23ce94fbe6d4bfcee7e591a1341cdc312e 06dd76859bc399d39aad460633b69cbaa6e8f94d
# Create a new branch with these backported commits.
git checkout -b backport-430-to-v13-branch
# Push it to GitHub.
git push --set-upstream origin backport-430-to-v13-branch
# Go back to the original working tree.
cd ../..
# Delete the working tree.
git worktree remove .worktrees/backport

Then, create a pull request where the base branch is v13-branch and the compare/head branch is backport-430-to-v13-branch.

[hm-backport]

The backport to v14-branch failed:

Commits ["3fc68c23ce94fbe6d4bfcee7e591a1341cdc312e","06dd76859bc399d39aad460633b69cbaa6e8f94d"] could not be cherry-picked on top of v14-branch

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub.
git fetch
# Create new working tree.
git worktree add .worktrees/backport v14-branch
# Navigate to the new directory.
cd .worktrees/backport
# Cherry-pick all the commits of this pull request and resolve the likely conflicts.
git cherry-pick 3fc68c23ce94fbe6d4bfcee7e591a1341cdc312e 06dd76859bc399d39aad460633b69cbaa6e8f94d
# Create a new branch with these backported commits.
git checkout -b backport-430-to-v14-branch
# Push it to GitHub.
git push --set-upstream origin backport-430-to-v14-branch
# Go back to the original working tree.
cd ../..
# Delete the working tree.
git worktree remove .worktrees/backport

Then, create a pull request where the base branch is v14-branch and the compare/head branch is backport-430-to-v14-branch.