Bump Apache Tika to 1.21

[tovbinm]

Related issues
Apache Tika 1.16 has numerous security vulnerabilities.

Describe the proposed solution
Bump Apache Tika to 1.21

Describe alternatives you've considered
NA

[codecov]

Codecov Report

Merging #331 into master will decrease coverage by 9.88%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #331      +/-   ##
==========================================
- Coverage   45.54%   35.66%   -9.89%     
==========================================
  Files         329      329              
  Lines       10617     6202    -4415     
  Branches      334      294      -40     
==========================================
- Hits         4836     2212    -2624     
+ Misses       5781     3990    -1791

Impacted Files	Coverage Δ
...ala/com/salesforce/op/testkit/InfiniteStream.scala	0% <0%> (-100%)	⬇️
...ce/op/stages/impl/feature/TextLenTransformer.scala	0% <0%> (-100%)	⬇️
...cala/com/salesforce/op/features/types/OPList.scala	0% <0%> (-100%)	⬇️
...n/scala/com/salesforce/op/readers/CSVReaders.scala	0% <0%> (-100%)	⬇️
.../scala/com/salesforce/op/readers/CSVDefaults.scala	0% <0%> (-100%)	⬇️
...om/salesforce/op/readers/DataFrameFieldNames.scala	0% <0%> (-100%)	⬇️
...a/com/salesforce/op/features/types/OPNumeric.scala	0% <0%> (-100%)	⬇️
...rce/op/stages/OpPipelineStageReadWriteShared.scala	0% <0%> (-100%)	⬇️
...es/sparkwrappers/specific/OpPredictorWrapper.scala	0% <0%> (-100%)	⬇️
...ages/base/sequence/BinarySequenceTransformer.scala	0% <0%> (-100%)	⬇️
... and 152 more

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[wsuchy]

LGTM

[salesforce-cla]

Thanks for the contribution! Before we can merge this, we need @tovbinm to sign the Salesforce.com Contributor License Agreement.