ci: fix escape flag in codecov

[hanxiao]

slash in flag is not escaped, seems like an upstream problem of codecov/codecov-action@v1

raised issue here: codecov/codecov-action#199

[codecov]

Codecov Report

Merging #1635 (e2c9e22) into master (e7ddd43) will decrease coverage by 7.70%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1635      +/-   ##
==========================================
- Coverage   80.66%   72.95%   -7.71%     
==========================================
  Files         126      126              
  Lines        6589     6589              
==========================================
- Hits         5315     4807     -508     
- Misses       1274     1782     +508     

Flag	Coverage Δ
3.7	?
cd	?
ci	72.95% <ø> (?)
core	72.95% <ø> (?)
integration	32.88% <ø> (?)
jinad	32.88% <ø> (?)
unit	?

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
jina/parsers/hub/pushpull.py	0.00% <0.00%> (-100.00%)	⬇️
jina/types/request/common.py	0.00% <0.00%> (-100.00%)	⬇️
jina/types/ndarray/sparse/numpy.py	0.00% <0.00%> (-100.00%)	⬇️
jina/types/ndarray/sparse/pytorch.py	0.00% <0.00%> (-100.00%)	⬇️
jina/types/ndarray/sparse/tensorflow.py	0.00% <0.00%> (-100.00%)	⬇️
jina/types/document/multimodal.py	34.00% <0.00%> (-64.00%)	⬇️
jina/executors/indexers/cache.py	34.28% <0.00%> (-61.43%)	⬇️
jina/executors/evaluators/embedding/cosine.py	36.66% <0.00%> (-56.67%)	⬇️
jina/executors/evaluators/embedding/euclidean.py	36.66% <0.00%> (-56.67%)	⬇️
jina/drivers/multimodal.py	36.11% <0.00%> (-55.56%)	⬇️
... and 56 more

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[github-actions]

Latency summary

Current PR yields:

• 😶 index QPS at 1696, delta to last 3 avg.: +0%
• 😶 query QPS at 32, delta to last 3 avg.: -1%

Breakdown

Version	Index QPS	Query QPS
current	1696	32
0.9.3	1685	32
0.9.2	1725	32
0.9.1	1687	32

Backed by latency-tracking. Further commits will update this comment.