Polish doc

Closes gh-1107

Author: nkjackzhang

src/asciidoc/core-beans.adoc

@@ -6520,7 +6520,7 @@ resulting bean. This functionality can be overridden, however, with the `name` a
 ==== Bean aliasing
 
 As discussed in <<beans-beanname>>, it is sometimes desirable to give a single bean
-multiple names, otherwise known as__bean aliasing__. The `name` attribute of the `@Bean`
+multiple names, otherwise known as __bean aliasing__. The `name` attribute of the `@Bean`
 annotation accepts a String array for this purpose.
 
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