Add missing stdio include. Depending on the CUnit lib version

Add missing stdio include.

Depending on the CUnit lib version, this could generate a build error of mindunit examples because of implicit declaration of fprintf.

For example, CUnit v2.1.2 is ok but CUnit v2.1.0 is KO...

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/home/ecp/mind4se-release-scripts/sh/mind4se-release/target/mind4se-compiler-0.1-SNAPSHOT/mind4se-compiler-0.1-SNAPSHOT/runtime/mindunit/mindUnitAutomated.c: In function '__component_mindunit_MindUnitAutomated_launchTests_testsLauncher':
/home/ecp/mind4se-release-scripts/sh/mind4se-release/target/mind4se-compiler-0.1-SNAPSHOT/mind4se-compiler-0.1-SNAPSHOT/runtime/mindunit/mindUnitAutomated.c:42:5: warning: incompatible implicit declaration of built-in function 'fprintf' [enabled by default]
/home/ecp/mind4se-release-scripts/sh/mind4se-release/target/mind4se-compiler-0.1-SNAPSHOT/mind4se-compiler-0.1-SNAPSHOT/runtime/mindunit/mindUnitAutomated.c:42:13: error: 'stderr' undeclared (first use in this function)
/home/ecp/mind4se-release-scripts/sh/mind4se-release/target/mind4se-compiler-0.1-SNAPSHOT/mind4se-compiler-0.1-SNAPSHOT/runtime/mindunit/mindUnitAutomated.c:42:13: note: each undeclared identifier is reported only once for each function it appears in