Adding ``travis_wait`` for timing out Travis CI jobs

[czgdp1807]

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[codecov[bot]]

Codecov Report

Merging #416 (42ae174) into master (9c6ed37) will decrease coverage by 0.028%. The diff coverage is n/a.

@@              Coverage Diff              @@
##            master      #416       +/-   ##
=============================================
- Coverage   98.634%   98.606%   -0.029%     
=============================================
  Files           26        26               
  Lines         3443      3516       +73     
=============================================
+ Hits          3396      3467       +71     
- Misses          47        49        +2     

Impacted Files	Coverage Δ
pydatastructs/trees/heaps.py	97.487% <0.000%> (-0.462%)	:arrow_down:
...datastructs/linear_data_structures/linked_lists.py	98.921% <0.000%> (-0.252%)	:arrow_down:
pydatastructs/graphs/algorithms.py	99.489% <0.000%> (-0.002%)	:arrow_down:
pydatastructs/strings/trie.py	100.000% <0.000%> (ø)
pydatastructs/graphs/adjacency_list.py	100.000% <0.000%> (ø)
pydatastructs/graphs/adjacency_matrix.py	100.000% <0.000%> (ø)
pydatastructs/linear_data_structures/arrays.py	100.000% <0.000%> (ø)
...datastructs/miscellaneous_data_structures/stack.py	100.000% <0.000%> (ø)
...ucts/miscellaneous_data_structures/disjoint_set.py	100.000% <0.000%> (ø)
...ts/miscellaneous_data_structures/binomial_trees.py	100.000% <0.000%> (ø)
... and 5 more