Update VERSION constant in 2.13 series

[phil-davis]

Q	A
Type	bug
BC Break	no
Fixed issues	#4711

Summary

Update the VERSION to be current.

[phil-davis]

Static Analysis fails because of:
"RedundantCast - lib/Doctrine/DBAL/Version.php:31:48 - The call to strtolower is unnecessary (see https://psalm.dev/262)"

When the constant VERSION has only numbers and dots, then strtolower() is unnecessary. But as soon as someone adds -DEV on the end, strtolower() will be necessary!

I guess that the code has to be adjusted every time -DEV is added/removed from the string. That's a maintenance headache!

For now, I will also push a commit to move VERSION up to 2.13.3-DEV.

[phil-davis]

Closing - see comments in issue. Can easily be re-opened if needed some time.