Change minimum SQL server to version 11 from 12

[simpleapps-io]

SQL Driver version 5.9 supports version 11+. SQL server 2012 is version 11 https://docs.microsoft.com/en-us/sql/connect/php/microsoft-php-drivers-for-sql-server-support-matrix?view=sql-server-ver15

[codecov]

Codecov Report

Merging #77 (2cbc8d5) into master (3a88162) will not change coverage.
The diff coverage is 50.00%.

@@            Coverage Diff            @@
##             master      #77   +/-   ##
=========================================
  Coverage     92.55%   92.55%           
  Complexity     1488     1488           
=========================================
  Files            67       67           
  Lines          3841     3841           
=========================================
  Hits           3555     3555           
  Misses          286      286           

Impacted Files	Coverage Δ
src/Driver/SQLServer/SQLServerDriver.php	86.00% <50.00%> (ø)

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