Restore default installed extensions/packages to ubuntu base (#445)

* Restore default installed extensions/packages to ubuntu base

* Add test for installing via legacy php.ini method

* Fix legacy extensions test directory

Fix the integration test. (#444)

The integration test uses a custom build pipeline. The build pipeline
now has extra arguments for the ubuntu image so we must provide them
here.

Run e2e test just once after ubuntu build (#440)

Fixed stackdriver integration (#434)

Change the way we check the required version of the dependency (#428)

There are still some cases for false negative where the direct
constrant is ok and other indirect dependency has a problem.

Although the issue is not completely fixed, this logic change allows
more legitimate cases which has been failing with the previous code.

It will alleviate #426

Change the way we check the required version of the dependency (#428)

There are still some cases for false negative where the direct
constrant is ok and other indirect dependency has a problem.

Although the issue is not completely fixed, this logic change allows
more legitimate cases which has been failing with the previous code.

It will alleviate #426

shorten tag name (#429)

lock redis extension to 3.1.6. 4.0.0 has breaking changes (#424)

Fix version check for building mongo (#421)

Fix version check for building mongo (#421)