just adding some quotes to server_version, couple of lines before is explained this: 

"Always wrap the server version number with quotes to parse it as a string instead of a float number"

…r explanation why are necessary (sergiosusa)

This PR was submitted for the 4.0 branch but it was merged into the 2.7 branch instead (closes #9815).

Discussion
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Adding quotes to a server_version on an example just after explanation why are necessary

just adding some quotes to server_version, couple of lines before is explained this:

"Always wrap the server version number with quotes to parse it as a string instead of a float number"

Commits
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3db34d4 Update doctrine.rst

This PR was merged into the 2.7 branch.

Discussion
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Corrected link to PHPUnit

Commits
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7c40f23 Corrected link to PHPUnit

* 2.5:
  Fixing build errors

* 2.6:
  Fixing build errors
  Fixing build errors