Update dependency dropdown_search to ^0.6.0

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
dropdown_search	dependencies	minor	^0.5.0 -> ^0.6.0

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Release Notes

salim-lachdhaf/searchable_dropdown

v0.6.3

• fix analyser issues

v0.6.2

• prop that passes all props to search field
• fix issues 169
• fix issues 163
• new Feature "dropdown BaseStyle" 178
• new Feature "popup scrollView"
• Ignore pointers in itemBuilder & cursor in web
• Added property to customize DropdownButton Splash Radius
• added property to set up the splash radius for clear button and for dropdown button in dropdown_search
• @​thanks Vasiliy

v0.6.1

• added property to set up the popup safe area
• fixed null safety issues

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Configuration

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