Fixes a crash when the value returned by Blog.version is not a string

[emilylaguna]

Sentry crash: https://sentry.io/organizations/a8c/issues/2511522132/events/?project=1438083

To test:

Verify the crash

1. Create a self hosted site that is not connected to Jetpack
2. Go to the My Site view
3. Tap the dropdown to view all your sites
4. Tap the + button to add a site
5. Tap Add Self Hosted
6. Add your new site
7. If the app doesn't crash:

Force the crash

1. Open Blog.m
2. Go to line: 449
3. Change it to return @5.5
4. This will force return an NSNumber
5. Relaunch the app
6. It should crash

Verify the fix

1. Remove the forced crash
2. Go to Blog.m
3. Line 902
4. Add a line above it for:

if([name isEqualToString:@"software_version"]){
    return @5.5;
}

This force returns an NSNumber for the software version
5. Relaunch the app
6. It should not crash

Regression Notes

1. Potential unintended areas of impact

• The BlogService calls [[blog version] floatValue]; since NSString implements this method this will not cause an issue.
• hasRequiredWordPressVersion in Blog.m expects a string anyways

2. What I did to test those areas of impact (or what existing automated tests I relied on)
   I did manual testing of that section.

3. What automated tests I added (or what prevented me from doing so)
   None.

PR submission checklist:

• I have completed the Regression Notes.
• I have considered adding unit tests for my changes.
• I have considered adding accessibility improvements for my changes.
• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary.

[peril-wordpress-mobile]

You can trigger an installable build for these changes by visiting CircleCI here.

[peril-wordpress-mobile]

You can trigger optional UI/connected tests for these changes by visiting CircleCI here.

[mokagio]

@chipsnyder @Gio2018 @leandroalonso 👋 folks! @emilylaguna was a legend in jumping onto this bugfix and ping me about it. I don't feel like I have too much context around this code to give a proper review, though, so I'm pinging you as per GitHub's suggestion. Feel free to bring more knowledgeable people in (blame GitHub if this ping is inappropriate 😝) Thanks!

For context the crash this PR fixes is something that is a new one in 17.7 and it's slowly but steadily rising in occurrences.

[mokagio]

@emilylaguna just dropping a note here in case something happens and I'm not able to followup: if we decide to proceed with the hotfix (as opposed to assess the occurrence of this issue "minor" and target the upcoming release instead) hotfix/17.7.1 is not the best place to merge this PR into.

A release manager, ideally me unless this escalates and I'm offline, will create a new hotfix release branch using the new_hotfix_release lane and take care of merging into it and shipping.

I had time to start the hotfix process and changed the base for this PR to release/17.7.1. Please note that whether this should be an hotfix is yet to be decided. I did all this to get ahead just in case we make that call.

[leandroalonso]

Reviewing it 👀

[leandroalonso]

I wasn't able to trigger the crash by adding a self-hosted site.

But following the test steps and playing with the value I was able to check correctness.

@emilylaguna this is a good opportunity to add unit tests for this change, ensuring that it works as expected and preventing any regression in the future. :)

[emilylaguna]

@leandroalonso good point! I'm adding tests now.

[emilylaguna]

@leandroalonso tests added: ea8b3e3

[emilylaguna]

@leandroalonso updated tests to include a test covering the "else" case: 741d128

[leandroalonso]

@emilylaguna 👌

[emilylaguna]

🥳 Will merge once build tests finish.

[mokagio]

@emilylaguna I noticed these typecast while looking over #16883.

I'm curious to know what made them necessary?

[emilylaguna]

Yeah, Xcode 12.5 was complaining about them.