fix: base64 encoding

[eschrewe]

Description

• added base64 encoding in frontend and decoding in backend for ownMaterialNumber values
• solves Potential problem with ownMaterialNumbers in request params of endpoints #494

Pre-review checks

Please ensure to do as many of the following checks as possible, before asking for committer review:

• DEPENDENCIES are up-to-date. Dash license tool. Committers can open IP issues for restricted libs.
• Copyright and license header are present on all affected files
• If helm chart has been changed, the chart version has been bumped to either next major, minor or patch level (compared to released chart).

[tom-rm-meyer-ISST]

Thanks for contributing. Beside the one comment, please also check on the following:

• Tests are failing for MaterialPartnerRelationsControllerTest and MaterialControllerTest.getMaterialTest()
• Controller for Days of supply also has unencoded material numbers
• Postman collection needs an update to use scripted value
• opening stock view throws an error (StockViewController.getCustomerProductStocks(StockViewController.java:476)

[tom-rm-meyer-ISST]

Thanks for the updates! Beside one test in the postman colleciton failing, opening Stock View, selecting tab Products leads to an error:

customer-backend        | java.lang.IllegalArgumentException: Last unit does not have enough valid bits
customer-backend        |       at java.base/java.util.Base64$Decoder.decode0(Unknown Source) ~[na:na]
customer-backend        |       at java.base/java.util.Base64$Decoder.decode(Unknown Source) ~[na:na]
customer-backend        |       at java.base/java.util.Base64$Decoder.decode(Unknown Source) ~[na:na]
customer-backend        |       at org.eclipse.tractusx.puris.backend.stock.controller.StockViewController.getSupplierMaterialStocks(StockViewController.java:438) ~[!/:2.0.2]
customer-backend        |       at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(Unknown Source) ~[na:na]
customer-backend        |       at java.base/java.lang.reflect.Method.invoke(Unknown Source) ~[na:na]

Please check

[tom-rm-meyer-ISST]

Postman collection works fine! Please check for the exception thrown when opening the stock view.

[tom-rm-meyer-ISST]

LGTM, pushed small coalescing change. Thanks for your work!