feat(contract-verifier): add compiler 1.5.6 (#3104)

## What ❔

add zksolc 1.5.6

## Why ❔

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## Checklist

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- [ ] Tests for the changes have been added / updated.
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lint`.

docker/contract-verifier/Dockerfile

@@ -47,7 +47,7 @@ RUN mkdir -p /etc/zksolc-bin/vm-1.5.0-a167aa3 && \
     chmod +x /etc/zksolc-bin/vm-1.5.0-a167aa3/zksolc
 
 # install zksolc 1.5.x
-RUN for VERSION in $(seq -f "v1.5.%g" 0 5); do \
+RUN for VERSION in $(seq -f "v1.5.%g" 0 6); do \
     mkdir -p /etc/zksolc-bin/$VERSION && \
     wget https://github.com/matter-labs/zksolc-bin/raw/main/linux-amd64/zksolc-linux-amd64-musl-$VERSION -O /etc/zksolc-bin/$VERSION/zksolc && \
     chmod +x /etc/zksolc-bin/$VERSION/zksolc; \