throw an exception if DSN is not set

[marandaneto]

📢 Type of change

• Bugfix
• New feature
• Enhancement
• Refactoring

📜 Description

throw an exception if DSN is not set.

💡 Motivation and Context

if DSN is not set, user needs to know right away, it might be a misconfiguration.

💚 How did you test it?

📝 Checklist

• I reviewed submitted code
• I added tests to verify changes
• All tests passing

🔮 Next steps

[codecov-io]

Codecov Report

Merging #200 into master will decrease coverage by <.01%.
The diff coverage is 0%.

@@             Coverage Diff              @@
##             master     #200      +/-   ##
============================================
- Coverage     57.94%   57.94%   -0.01%     
- Complexity      547      548       +1     
============================================
  Files            72       72              
  Lines          2611     2613       +2     
  Branches        227      228       +1     
============================================
+ Hits           1513     1514       +1     
- Misses          981      983       +2     
+ Partials        117      116       -1

Impacted Files	Coverage Δ	Complexity Δ
...ntry-core/src/main/java/io/sentry/core/Sentry.java	0% <0%> (ø)	0 <0> (ø)	⬇️
...c/main/java/io/sentry/core/DirectoryProcessor.java	74.07% <0%> (+3.7%)	7% <0%> (+1%)	⬆️

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[bruno-garcia]

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