Revert #3688 config-center-config

[chickenlj]

What is the purpose of the change

see issue described here #3682

Brief changelog

XXXXX

Verifying this change

XXXXX

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[chickenlj]

/**
     * if {@link #key()} is specified, it will be used as the key for the annotated property when generating url.
     * by default, this key will also be used to retrieve the config value:
     * <pre>
     * {@code
     *  class ExampleConfig {
     *      // Dubbo will try to get "dubbo.example.alias_for_item=xxx" from .properties, if you want to use the original property
     *      // "dubbo.example.item=xxx", you need to set useKeyAsProperty=false.
     *      @Parameter(key = "alias_for_item")
     *      public getItem();
     *  }
     * }
     *
     * </pre>
     */
    boolean useKeyAsProperty() default true;	    boolean useKeyAsProperty() default true;

[chickenlj]

class ExampleConfig {
      // Dubbo will try to get "dubbo.example.alias_for_item=xxx" from .properties, if you want to use the original property
     // "dubbo.example.item=xxx", you need to set useKeyAsProperty=false.
     @Parameter(key = "alias_for_item")
    public getItem() {
      return "xxx";
    }
}

Only key is set or not matters:

URL: dubbo://xxxxx?alias_for_item=xxxx

# when useKeyAsProperty=true.
dubbo.example.alias_for_item=xxx
# useKeyAsProperty=false.
dubbo.example.item=xxx

[ralf0131]

I got what you mean, I think it is reasonable to revert it.

[ralf0131]

@tswstarplanet Could you please verify it?

[ralf0131]

@tswstarplanet I am merging it, please feel free to reopen this, if you have any issues.