Count the number of fields in each csv record
Stax, 19 12 bytes

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Unpacked, ungolfed, and commented, it looks like this.

_'"/    split *all* of standard input by double quote characters
2::     keep only the even numbered elements
|j      split on newlines (implicitly concatenates array of "strings")
m       for each line, execute the rest of the program and output
  ',#^  count the number of commas occurring as substrings, and increment


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