Fix implementation of reactive URL in OracleService

[jsmrcka]

Current implementation

    @Override
    public String getReactiveUrl() {
        return getHost().replace("http://", getJdbcName() + ":thin:@") + ":" + getPort() + ":" + getDatabase();
    }

should be replaced with

    @Override
    public String getReactiveUrl() {
        return getHost().replace("http://", getJdbcName() + ":thin:@") + ":" + getPort() + "/" + getDatabase();
    }

(colon : replaced by slash /).

Proper syntax of reactive URL for Oracle DB is documented only partially.

• https://quarkus.io/version/main/guides/reactive-sql-clients
• https://quarkus.io/version/main/guides/datasource

An issue to clarify the topic: quarkusio/quarkus#26426.

As part of the implementation change, add test coverage for reactive URL.

Follow-up to:
#428
#489

[michalvavrik]

I checked all getReactiveUrl() and can't find any with that colon anymore, so I'll go ahead and close the issue.