url encode monitor IDs in SA receiver

[rmfitzpatrick]

Receiver creator instantiated names have quotes in them, which breaks collectd instance templating:
<Instance "[monitorID=receiver_creatorsmartagentnginx{endpoint="172.17.0.2:8080"}]">

These changes url encode the monitor name for monitor id usage instead of simply removing forward slashes.

[codecov]

Codecov Report

Merging #266 (d03b62a) into main (d6b531d) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main     #266   +/-   ##
=======================================
  Coverage   86.91%   86.91%           
=======================================
  Files          20       20           
  Lines        1490     1490           
=======================================
  Hits         1295     1295           
  Misses        160      160           
  Partials       35       35           

Impacted Files	Coverage Δ
internal/receiver/smartagentreceiver/receiver.go	91.89% <100.00%> (ø)

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