new: dev: add unit tests for cache config utility methods

Pull Request Test Coverage Report for Build 74

111 of 159 (69.81%) changed or added relevant lines in 13 files are covered.
2 unchanged lines in 2 files lost coverage.
Overall coverage increased (+1.3%) to 22.311%

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
rubix-spi/src/main/java/com/qubole/rubix/spi/DataTransferClientHelper.java	0	1	0.0%
rubix-bookkeeper/src/main/java/com/qubole/rubix/bookkeeper/LocalDataTransferServer.java	0	1	0.0%
rubix-bookkeeper/src/main/java/com/qubole/rubix/bookkeeper/DiskMonitorService.java	0	1	0.0%
rubix-core/src/main/java/com/qubole/rubix/core/CachingFileSystem.java	0	1	0.0%
rubix-spi/src/main/java/com/qubole/rubix/spi/CacheUtil.java	85	87	97.7%
rubix-core/src/main/java/com/qubole/rubix/core/CachingInputStream.java	0	2	0.0%
rubix-bookkeeper/src/main/java/com/qubole/rubix/bookkeeper/FileMetadata.java	0	2	0.0%
rubix-bookkeeper/src/main/java/com/qubole/rubix/bookkeeper/utils/DiskUtils.java	0	2	0.0%
rubix-bookkeeper/src/main/java/com/qubole/rubix/bookkeeper/BookKeeper.java	0	5	0.0%
rubix-bookkeeper/src/main/java/com/qubole/rubix/bookkeeper/BookKeeperServer.java	0	5	0.0%
<!--	Total:	111	159	69.81%	-->

Files with Coverage Reduction	New Missed Lines	%
rubix-bookkeeper/src/main/java/com/qubole/rubix/bookkeeper/utils/DiskUtils.java	1	0.0%
rubix-core/src/main/java/com/qubole/rubix/core/CachingInputStream.java	1	0.0%
<!--	Total:	2	-->