Switch log level for cyclic reference index warnings from WARN to INFO. [DATAMONGO-1124]

[spring-projects-issues]

Christoph Strobl opened DATAMONGO-1124 and commented

The warning seems to be cause of confision and frustration so we should lower the log level to reduce noise

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Issue Links:

• DATAMONGO-1121 "Cycle found" false positive

Referenced from: pull request #282

Backported to: 1.6.3 (Evans SR3)