Added spec test for increase_decrease_capacity test

[macaktom]

Description

Added pass/happy scenario spec test for increase_decrease_test. Tested by running all spec tests in configuration_spec.cr file. Also tested individually when running spec test with "increase_decrease_capacity" tag.

Issues:

Refs: #1436

Types of changes:

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

Checklist:

Documentation

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• No updates required.

Code Review

• Does the test handle fatal exceptions, ie. rescue block

Issue

• Tasks in issue are checked off

[taylor]

lgtm

[agentpoyo]

LGTM