`@as` attribute not required in `<o/>` elements within `<o base="..">` elements

[yegor256]

Let's make @as attribute mandatory of <o/> elements that stay inside <o base=".."> (with the @base attribute).

Motivation: objectionary/phino#200 and objectionary/jeo-maven-plugin#1174

[h1alexbel]

@yegor256 currently, EO-parser does not add @as to the applications:

<o base="$.^.x.put" line="30" pos="21">
   <o base="$.^.x.as-number.plus" line="31" pos="33">
      <o base="Q.org.eolang.number" line="31" pos="39">
         <o base="Q.org.eolang.bytes" line="31" pos="39">
            <o line="31" pos="39">3F-F0-00-00-00-00-00-00</o>
         </o>
      </o>
   </o>
</o>

Should we ignore this for now and unlint it in several places, or I missing something?

[yegor256]

@h1alexbel we should fix the parser, I believe