fix running default compilation

apps/solidity-compiler/src/app/compiler-api.ts

@@ -330,6 +330,7 @@ export const CompilerApiMixin = (Base) => class extends Base {
         e.preventDefault()
         if(await this.getAppParameter('hardhat-compilation')) this.compileTabLogic.runCompiler('hardhat')
         else if(await this.getAppParameter('truffle-compilation')) this.compileTabLogic.runCompiler('truffle')
+        else this.compileTabLogic.runCompiler(undefined)
       }
     }
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