Admin menu module - fix preset modern for postgresql

[csthomas]

Summary of Changes

Fix sql error in postgresql database in admin menu.

Testing Instructions

Error exists only on postgresql.

Before patch

After patch

[alikon]

I have tested this item ✅ successfully on 1471f13

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[csthomas]

As my change is equal to the same line in

joomla-cms/administrator/components/com_menus/presets/joomla.xml

Line 213 in 54eb5d8

sql_group="a.id, m.language, l.image"

another test may be done by code review or by test on mysql only.

[ghost]

I have tested this item ✅ successfully on 1471f13

System information

3.8.3-dev
Multilanguage Site (4 Lang.) & Sample Data
macOS Sierra, 10.12.6
Firefox 57 (64-bit)

MAMP 4.2

• PHP 7.0.22
• MySQLi 5.6.35

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[ghost]

Ready to Commit after two successful tests.