Adding "weights" param for combination technique

[martin-gaievski]

Description

Adding parameter "weights" for combination technique in normalization processor. Weights are use to multiply scores for each sub-query from the Hybrid search query. Weights are mapped to sub-query based on position (index), if there are less weights provided we use "1.0" for the rest of sub-query scores. If there are more weights provided we take first N and ignore the rest.

Parameter is set as part of the search pipeline, example of such request:

{
    "description": "Post processor for hybrid search",
    "phase_results_processors": [
        {
            "normalization-processor": {
                "normalization": {
                    "technique": "min_max"
                },
                "combination": {
                    "technique": "arithmetic_mean",
                    "parameters": {
                        "weights": [
                            0.4, 0.7
                        ]
                    }
                }
            }
        }
    ]
}

Issues Resolved

#228, part of solution for #126

Check List

• All tests pass
• New functionality has javadoc added
• Commits are signed as per the DCO using --signoff

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[codecov]

Codecov Report

Merging #234 (de773ff) into feature/normalization (2224f1f) will decrease coverage by 0.48%.
The diff coverage is 75.00%.

@@                     Coverage Diff                     @@
##             feature/normalization     #234      +/-   ##
===========================================================
- Coverage                    85.55%   85.07%   -0.48%     
- Complexity                     296      304       +8     
===========================================================
  Files                           24       24              
  Lines                          872      898      +26     
  Branches                       134      139       +5     
===========================================================
+ Hits                           746      764      +18     
- Misses                          67       70       +3     
- Partials                        59       64       +5     

Files Changed	Coverage Δ
...ation/ArithmeticMeanScoreCombinationTechnique.java	69.69% <66.66%> (-10.31%)	⬇️
...processor/combination/ScoreCombinationFactory.java	100.00% <100.00%> (ø)
...ocessor/factory/NormalizationProcessorFactory.java	100.00% <100.00%> (ø)