fix: add query support for entities with @EmbeddedId attribute

[igdianov]

This PR adds query support for entitites with @EmbeddedId attributes, i.e. given:

@Data
@Entity
public class Book {

    @EmbeddedId
    private BookId bookId;

    private String description;
} 

with embedded id attribute

@Data
@Embeddable
public class BookId implements Serializable {
    private static final long serialVersionUID = 1L;

    private String title;
    private String language;
} 

then, use query with embedded id:

query {
  Books( 
    where: {
      bookId: {
        EQ: {
          title:  "War and Piece"
          language:  "Russian"
        }
      }
    }
  ){
    total
    pages
    select {
      bookId {
        title
        language
      }
      description
    }
  }
}

[codecov]

Codecov Report

Merging #180 into master will increase coverage by 0.28%.
The diff coverage is 88.46%.

@@             Coverage Diff              @@
##             master     #180      +/-   ##
============================================
+ Coverage     68.54%   68.83%   +0.28%     
- Complexity      511      516       +5     
============================================
  Files            33       33              
  Lines          2639     2663      +24     
  Branches        432      436       +4     
============================================
+ Hits           1809     1833      +24     
+ Misses          665      664       -1     
- Partials        165      166       +1

Impacted Files	Coverage Δ	Complexity Δ
...hql/jpa/query/schema/impl/JpaPredicateBuilder.java	56.47% <100%> (+0.6%)	108 <0> (ø)	⬇️
...a/query/schema/impl/QraphQLJpaBaseDataFetcher.java	75.85% <88%> (+0.53%)	166 <4> (+5)	⬆️

---

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[codecov]

Codecov Report

Merging #180 into master will increase coverage by 0.28%.
The diff coverage is 88.46%.

@@             Coverage Diff              @@
##             master     #180      +/-   ##
============================================
+ Coverage     68.54%   68.83%   +0.28%     
- Complexity      511      516       +5     
============================================
  Files            33       33              
  Lines          2639     2663      +24     
  Branches        432      436       +4     
============================================
+ Hits           1809     1833      +24     
+ Misses          665      664       -1     
- Partials        165      166       +1

Impacted Files	Coverage Δ	Complexity Δ
...hql/jpa/query/schema/impl/JpaPredicateBuilder.java	56.47% <100%> (+0.6%)	108 <0> (ø)	⬇️
...a/query/schema/impl/QraphQLJpaBaseDataFetcher.java	75.85% <88%> (+0.53%)	166 <4> (+5)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 50df533...e5a5444. Read the comment docs.