Retain filtered month in archive form

[Quy]

This is a partial fix for Issue #19382.

Summary of Changes

In the Archive search form, the month dropdown has leading zero from Jan. to Sep.

<select id="month" name="month" size="1" class="inputbox">
	<option value="">Month</option>
	<option value="01">Jan</option>
	<option value="02">Feb</option>
	<option value="03">Mar</option>
	<option value="04">Apr</option>
	<option value="05">May</option>
	<option value="06">Jun</option>
	<option value="07">Jul</option>
	<option value="08">Aug</option>
	<option value="09">Sep</option>
	<option value="10">Oct</option>
	<option value="11">Nov</option>
	<option value="12">Dec</option>
</select>

This PR removes the leading zero to match the month query string so the chosen month is selected:
http://localhost/joomla-cms-staging/archived-articles/2011?view=archive&month=1

Testing Instructions

Install demo.
Click Archive link.
Click January, 2011.
In the archive form, see the month dropdown.

Expected result

Jan is selected.

Actual result

Month is selected.

Documentation Changes Required

none

[ghost]

I have tested this item ✅ successfully on a7e550d

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_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/19391.}

[alikon]

I have tested this item ✅ successfully on a7e550d

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_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/19391.}

[ghost]

Ready to Commit after two successful tests.