Remove html tags in README markdown

[cosmicBboy]

They show up in the pypi page: https://pypi.org/project/flytekit/

TL;DR

Please replace this text with a description of what this PR accomplishes.

Type

• Bug Fix
• Feature
• Plugin

Are all requirements met?

• Code completed
• Smoke tested
• Unit tests added
• Code documentation added
• Any pending items have an associated Issue

Complete description

How did you fix the bug, make the feature etc. Link to any design docs etc

Tracking Issue

https://github.com/flyteorg/flyte/issues/

Follow-up issue

NA
OR
https://github.com/flyteorg/flyte/issues/

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.67%. Comparing base (d817f27) to head (de547a3).
Report is 1032 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1083   +/-   ##
=======================================
  Coverage   86.67%   86.67%           
=======================================
  Files         269      269           
  Lines       25074    25074           
  Branches     2826     2826           
=======================================
  Hits        21734    21734           
  Misses       2871     2871           
  Partials      469      469           

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