Add UI improvement to support mutual SSL authentication under KM configurations

[RusJaI]

For IS 7.1 we are supporting tenant sharing feature. For that we use certificate based authenthentication to communicate between APIM and IS, for a created tenant.
This fix is intended to facilitate with the same capability on the UI.
This involves the following changes :

• previously we maintained a flat json structure for all available key manager configurations
• with this, we have 2 authentication options : either basic auth or MTLS.
• if basic auth is selected, user have to provide username and password as previously.
• if MTLS was selected user have to either select server wide cert or tenant wide cert
• if server wide cert is selected it will use the existing certificate which is currently trusted by both APIM and IS truststores
• if tenantwide certificate is selected, user can upload a certificate which is trusted by the identity server, using the drop box provided on this UI. the main aim of this is to prove an option to user to add new certificates using the UI itself.
• based on the authentication type selected, DCR client will be initialized accordingly

[sonarqubecloud]

Quality Gate passed

Issues
16 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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