Adjust for daylight savings in String#to_time

The changes in b79adc4323 had a bug where if the time in the String
was in standard time but the current time was in daylight savings then
the calculated adjustment was off by an hour.

This commit fixes this and adds extra tests for the following:

* time in string is standard time, current time is standard time
* time in string is standard time, current time is daylight savings
* time in string is daylight savings, current time is standard time
* time in string is daylight savings, current time is daylight savings

Fixes #10306.
When empty options passed to having clause having_values was [nil] but should be empty.
refactor initialization of array
Merge pull request #10318 from vipulnsward/refactor_obvious

refactor initialization of array
Merge pull request #10317 from arabonradar/ar_having_values_bug_fix

ActiveRecord having clause bug fix
Revert "`belongs_to :touch` behavior now touches old association when transitioning to new association" until a proper fix is found for #10197
Remove test case also related to the belongs_to touch feature
Add test for `format: false` with resources - closes #10323
fixed missing comma in example
Merge pull request #10324 from prijutme4ty/guides_fix

fixed missing comma in example
Revert "Revert "`belongs_to :touch` behavior now touches old association when transitioning to new association" until a proper fix is found for #10197"

This reverts commit 7389df139a35436f00876c96d20e81ba23c93f0a.

Conflicts:
	activerecord/test/cases/timestamp_test.rb
added test cases for #10197
Reset the primary key for other tests
Removed unused associations
Lookup the class at runtime, not when the association is built

Trying to lookup the parent class when the association is being built
runs the risk of generating uninitialized constant errors because
classes haven't been fully defined yet. To work around this we look up
the class at runtime through the `association` method.

Fixes #10197.