Change a method name to make consistent with PR#6801

[T45K]

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In #6801, a method name, FlowableZipIterable#error is changed to fail, but its similar class, ObservableZipIterable was not changed.
I changed it for consistency.

• Please include the issue list number(s) or other PR numbers in the description if you are contributing in response to those.

This PR is related to #6801

• Please include a reasonable set of unit tests if you contribute new code or change an existing one. If you contribute an operator, (if applicable) please make sure you have tests for working with an empty, just, range of values as well as an error source, with and/or without backpressure and see if unsubscription/cancellation propagates correctly.

This change will not affect external behavior.

[codecov]

Codecov Report

Merging #7080 into 3.x will decrease coverage by 0.01%.
The diff coverage is 100.00%.

@@             Coverage Diff              @@
##                3.x    #7080      +/-   ##
============================================
- Coverage     99.51%   99.49%   -0.02%     
  Complexity     6667     6667              
============================================
  Files           742      742              
  Lines         47275    47275              
  Branches       6374     6374              
============================================
- Hits          47044    47037       -7     
- Misses          105      110       +5     
- Partials        126      128       +2     

Impacted Files	Coverage Δ	Complexity Δ
...al/operators/observable/ObservableZipIterable.java	100.00% <100.00%> (ø)	3.00 <0.00> (ø)
.../operators/observable/ObservableFlatMapSingle.java	94.44% <0.00%> (-3.18%)	2.00% <0.00%> (ø%)
...va/io/reactivex/rxjava3/subjects/MaybeSubject.java	97.75% <0.00%> (-2.25%)	45.00% <0.00%> (-1.00%)
.../internal/disposables/ListCompositeDisposable.java	98.00% <0.00%> (-2.00%)	34.00% <0.00%> (-1.00%)
...tivex/rxjava3/disposables/CompositeDisposable.java	98.14% <0.00%> (-1.86%)	39.00% <0.00%> (-1.00%)
...internal/operators/flowable/FlowableFromArray.java	96.61% <0.00%> (-1.70%)	3.00% <0.00%> (ø%)
...java3/internal/operators/flowable/FlowableZip.java	98.97% <0.00%> (-1.03%)	6.00% <0.00%> (ø%)
...a3/internal/operators/flowable/FlowableCreate.java	98.05% <0.00%> (-0.98%)	6.00% <0.00%> (ø%)
...operators/observable/ObservableMergeWithMaybe.java	99.09% <0.00%> (-0.91%)	2.00% <0.00%> (ø%)
...a3/internal/operators/flowable/FlowableReplay.java	98.92% <0.00%> (-0.86%)	21.00% <0.00%> (ø%)
... and 11 more

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