fix: use .sonarcloud.properties for SonarCloud Automatic Analysis

sonar-project.properties is read by CI/scanner-based analysis;
SonarCloud's Automatic Analysis mode (what this project uses - no
scanner invocation exists in any workflow) reads .sonarcloud.properties
instead, which is why the S1313 issue-ignore rule from the previous
commit had no effect (5207 code smells, unchanged). Also drops
sonar.projectKey/sonar.organization, which automatic analysis doesn't
support overriding, and simplifies the resourceKey glob from
tests/test_operators/**/*.py to tests/test_operators/*.py to match the
documented working pattern (both directories are flat, no ** needed).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

Author: fzipi