[mysql] fix: ensure span name is a string to avoid [object Object] as span name

[naseemkullah]

Which problem is this PR solving?

• [mysql] span name [object Object] #206

Short description of the changes

• Ensured that the span name is always a string. The approach differs when the query is a string vs an object:

  • for string, use the verb
  • for an object, use the sql string without the templated variable

• Also replaced deprecated equals method in tests

[codecov]

Codecov Report

Merging #208 into master will decrease coverage by 0.25%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #208      +/-   ##
==========================================
- Coverage   95.20%   94.94%   -0.26%     
==========================================
  Files          92       79      -13     
  Lines        4731     4236     -495     
  Branches      491      432      -59     
==========================================
- Hits         4504     4022     -482     
+ Misses        227      214      -13     

Impacted Files	Coverage Δ
node/opentelemetry-plugin-mysql/src/utils.ts	100.00% <0.00%> (ø)
node/opentelemetry-plugin-express/.eslintrc.js
...lemetry-propagator-grpc-census-binary/.eslintrc.js
node/opentelemetry-plugin-express/src/version.ts
...grpc-census-binary/test/BinaryTraceContext.test.ts
node/opentelemetry-plugin-express/src/types.ts
node/opentelemetry-plugin-express/src/express.ts
...pc-census-binary/test/GrpcCensusPropagator.test.ts
...tor-grpc-census-binary/src/GrpcCensusPropagator.ts
...de/opentelemetry-plugin-express/test/utils.test.ts
... and 5 more

[obecny]

Nit: can you reverse the logic in test

describe('when the query is a string', ()=> {
  it('span should have correct name', ...) 
})

describe('when the query is a an object', ()=> {
  it('span should have correct name', ...) 
})

[naseemkullah]

that does read better!

[obecny]

@naseemkullah just a gently ping on this :)

[naseemkullah]

pong!

Sorry dropped the ball on this :)