[FIX] web: remove duplicate classname in RecordSelector

This commit removes the unnecessary duplicate of the 'o-input' class being present
in the template of the (Multi)RecordSelector components. As the RecordAutocomplete
component uses the Autocomplete component, which already set this classname on its
<input> node, the class was present twice in the DOM.

This could affect the style when trying to write a rule on .o_input since both elements
would get the style.

Now, only the input keep the class, which makes things easier and more predictable.

closes odoo/odoo#161934

Signed-off-by: Mathieu Duckerts-Antoine (dam) <dam@odoo.com>

addons/web/static/src/core/record_selectors/multi_record_selector.xml

@@ -9,7 +9,7 @@
                 value="''"
                 domain="props.domain"
                 context="props.context"
-                className="'o_input flex-grow-1'"
+                className="'flex-grow-1'"
                 fieldString="props.fieldString"
                 placeholder="placeholder"
                 multiSelect="true"

addons/web/static/src/core/record_selectors/record_selector.xml

@@ -7,7 +7,7 @@
             value="displayName"
             domain="props.domain"
             context="props.context"
-            className="'o_input h-100 o_record_selector'"
+            className="'h-100 o_record_selector'"
             fieldString="props.fieldString"
             placeholder="props.placeholder"
             multiSelect="false"