[lib/env] Remove noisy DBG statement

That debug statement is noisy, as it is emitted all the time,
irregardless whether or not the environment variable is set.

emper/lib/env.hpp

@@ -10,7 +10,6 @@
 namespace emper::lib::env {
 
 static auto getBoolFromEnv(const std::string& key) -> std::optional<bool> {
-	DBG("parse " << key << " environment variable");
 	char* envVar = std::getenv(key.c_str());
 	if (!envVar) {
 		return std::nullopt;
@@ -30,7 +29,6 @@ static auto getBoolFromEnv(const std::string& key) -> std::optional<bool> {
 
 template <typename unsigned_type>
 static auto getUnsignedFromEnv(const std::string& key) -> std::optional<unsigned_type> {
-	DBG("parse " << key << " environment variable");
 	char* envVar = std::getenv(key.c_str());
 	if (!envVar) {
 		return std::nullopt;