Fix deprecations in the Spotless build.

Author: nedtwigg

build.gradle

@@ -22,7 +22,7 @@ spotless {
 	}
 	format 'dotfiles', {
 		target '.gitignore', '.gitattributes', '.editorconfig'
-		indentWithSpaces(2)
+		leadingTabsToSpaces(2)
 		trimTrailingWhitespace()
 		endWithNewline()
 	}

gradle/spotless-freshmark.gradle

@@ -10,7 +10,7 @@ Action<FreshMarkExtension> freshmarkSetup = {
 		it.put('yes', ':+1:')
 		it.put('no', ':white_large_square:')
 	}
-	it.indentWithSpaces(2)
+	it.leadingTabsToSpaces(2)
 	it.endWithNewline()
 }