CORE-3594 Automatic dropping of default values on MS SQL

[pom75]

https://liquibase.jira.com/projects/CORE/issues/CORE-3594

Error Message During Column Drop with Default Value

{CODE}
RROR Reason: liquibase.exception.DatabaseException: Error executing SQL ALTER TABLE TEST DROP COLUMN COL2: The object 'DF_GENERIC_ENTITY_COL2' is dependent on column 'COL2'.
{CODE}

Steps to Reproduce

1. Create a changelog with the following changes:
   {CODE}

<changeSet id="C2" labels="dropColumnWithDefaultValue>


{CODE}
2. Execute a Liquibase update to deploy C1 to a SQL Server database:
{CODE}
liquibase --changeLogFile=mychangelog.xml --labels=columnWithDefaultValue update
{CODE}
3. Execute a second Liquibase update to deploy C2:
{CODE}
liquibase --changeLogFile=mychangelog.xml --labels=dropColumnWithDefaultValue update
{CODE}

Expected Results

There is no error dropping the column.

Actual Results

The error identified earlier in the description is output during dropColumn execution.

Manual Test Criteria

• Validate the bug is reproducible following the Repro steps.
• Do a desk check with the developer.
• Verify the fix works on your machine.

Automated Test Criteria

• Write an MSSQL regression test
  • Name: Drop column does not fail for a column with a default value.
  • Description: Ticket number.

┆Issue is synchronized with this Jira Bug by Unito
┆fixVersions: Community 4.x,Liquibase 4.3.0

[SteveDonie]

Thanks for the pull request and for including tests!

Here’s what happens next:

A member of the Liquibase team will take a look at your contribution and may suggest changes, additional tests, or provide other feedback. The PR will be prioritized according to our internal development and testing capacity.
We’ll let you know when it’s ready to move to the next step or if any changes are needed.

Thanks again!

[ro-rah]

closes #CORE-3594

[ro-rah]

I see this was already in the backlog, so I am going to push this PR along internally.