Handle i386 test failure due to types

[shntnu]

replicate_correlation tests fail due to something related to data frame casting

1. Failure: `replicate_correlation` measure correlation between replicates in each feature (@test-replicate_correlation.R#57) 
`%>%`(...) not equal to `correlations`.
Rows in x but not y: 3. Rows in y but not x: 3. 

2. Failure: `replicate_correlation` measure correlation between replicates in each feature (@test-replicate_correlation.R#68) 
`%>%`(...) not equal to `correlations`.
Rows in x but not y: 3. Rows in y but not x: 3. 

Casting operands as.data.frame solves the problem; not sure why

[shntnu]

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