fix typo, wording

[clsung]

• trivial

[codecov-io]

Codecov Report

Merging #289 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #289   +/-   ##
=======================================
  Coverage   85.74%   85.74%           
=======================================
  Files          33       33           
  Lines        1620     1620           
  Branches      183      183           
=======================================
  Hits         1389     1389           
  Misses        184      184           
  Partials       47       47

Impacted Files	Coverage Δ
...ntelemetry-api/src/opentelemetry/trace/__init__.py	87.9% <ø> (ø)	⬆️
.../context/propagation/tracecontexthttptextformat.py	84.5% <ø> (ø)	⬆️

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[codeboten]

👍

[mauriciovasquezbernal]

I pushed a new commit to this PR to fix also a typo on the Jaeger exporter: https://github.com/open-telemetry/opentelemetry-python/pull/174/files#r346584242, I didn't want to make that much noise opening a PR just for a typo.