Categorize invalid argument errors to approx_percentile
Fix parsing and formatting of sign expressions
Rename legacy config name in development properties
Deprecate the datasources configuration property

This property, if not set, is now configured automatically at startup based
on the list of installed catalogs.  This will be completely removed later.
Fix tests for datasources change
Add 0.69 release notes
[maven-release-plugin] prepare release 0.69
[maven-release-plugin] prepare for next development iteration
Rewrite EXPLAIN to a VALUES query

This helps avoid bytecode generation failures when plan string is too large due
to max constant pool size being exceeded.
Remove use of dual metadata from interpreter tests
Remove use of dual connector from TestSqlStageExecution
Remove use of dual from TestSqlTaskExecution
Remove use of dual from TestSqlTaskManager
Remove use of dual from query and function tests
Remove use of dual from TestEffectivePredicateExtractor
Remove dual connector
Optimize imports
Fix failing unit test in java 8

The user.timezone property for the surefire plugin must match
the setting via argLine. The pom was inheriting the property from
airbase set to UTC, but argLine was set to Asia/Katmandu.

As far as I can tell, the surefire plugin executes the following steps:
- create a VM using the argLine arguments
- call setProperty for each systemPropertyVariable
- run the tests

Unlike Java 7, calling System.setProperty for user.timezone in Java 8 after the
 VM is initialized has no effect. See d2fee8d93952054883bf94a65576cead632314cf
for additional details
Fix failing unit test in java 8

The expected stack overflow error occurs in the parser instead of in the analyzer in Java 8
Remove duplicate dependency