Fix entity naming mechanism failure in MAL

[wu-sheng]

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Fix entity(service/instance/endpoint) names in the MAL system(prometheus, native meter, open census, envoy metric service) are not controlled by core's naming-control mechanism.

[hanahmily]

LGTM

[kezhenxu94]

This fix is fragile, MeterEntity exposes many means to construct its instances, this patch only covers the static methods newService, newServiceInstance, newEndpoint, newServiceRelation, future developers who use the uncovered cases to construct the entity might cause the bug again.

The other uncovered cases:

1. MeterEntity.builder().serviceName("").instanceName("")..., if it's designed to only use the newXxxx methods to construct MeterEntity, we should update the @Builder annotation to @Builder(toBuilder = true, access = AccessLevel.PRIVATE)
2. meterEntity.toBuilder() returns another builder, which is the same case with (1.), we'd better also remove toBuilder = true in @Builder
3. new constructor (although it's package-private), we'd better also make it private.

[wu-sheng]

@kezhenxu94 I removed @Builder and fixed the tests.