Remove false from result of "returning" methods in CommandInterface

[vjik]

Q	A
Is bugfix?	❌
New feature?	❌
Breaks BC?	✔️

An exception will be thrown if the command fails.

Related PRs:

• Remove false from result of "returning" methods in CommandInterface db-mysql#437
• Remove false from result of "returning" methods in CommandInterface db-oracle#372
• Remove result from ActiveRecordInterface methods: insert, upsert, save active-record#485

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.52%. Comparing base (bc14f89) to head (a556804).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #1081      +/-   ##
============================================
+ Coverage     98.49%   98.52%   +0.02%     
+ Complexity     1658     1657       -1     
============================================
  Files           118      118              
  Lines          4265     4264       -1     
============================================
  Hits           4201     4201              
+ Misses           64       63       -1     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[Tigrov]

There are cases when it can return false

1. $attributes = [PDO::ATTR_ERRMODE => PDO::ERRMODE_SILENT]; or PDO::ERRMODE_WARNING
   https://github.com/yiisoft/db-pgsql/blob/e175847840023aa5c824c77ad2f6d32709671763/src/Driver.php#L19
2. Not PDO connection in future