[0.4.2] Improvements and bug fix

Internal:

• Bug fix for nonce config property initialization inside KeyShareApiService and unit tests.

Improvements:

• Added index on key_material_share_nonce table columns to increase query performance

Maven package versions:

cdoc2-shares-server-pom 0.2.0
cdoc2-shares-server 0.4.2
cdoc2-css-db 0.1.2
cdoc2-css-openapi 0.1.1