sonic-eventd: Use json.hpp from nlohmann-json3-dev instead of swss-common (#16818)

#### Why I did it

This header file comes from an external package, and a very old version of the header file has been checked into swss-common. This will cause problems for the upcoming Bookworm upgrade.

##### Work item tracking
- Microsoft ADO **(number only)**: 25411155

#### How I did it

Change references to the header file to use the Debian package nlohmann-json-dev, instead of from swss-common.

### Tested branch (Please provide the tested image version)

- [ ] <!-- image version 1 -->
- [ ] VS image from pipeline build

Verified that eventd was running

src/sonic-eventd/rsyslog_plugin/rsyslog_plugin.cpp

@@ -5,7 +5,7 @@
 #include <ctime>
 #include <unordered_map>
 #include "rsyslog_plugin.h"
-#include "json.hpp"
+#include <nlohmann/json.hpp>
 
 using json = nlohmann::json;
 
@@ -56,7 +56,7 @@ bool RsyslogPlugin::createRegexList() {
     }
     try {
         regexFile >> jsonList;
-    } catch (invalid_argument& iaException) {
+    } catch (nlohmann::detail::parse_error& iaException) {
         SWSS_LOG_ERROR("Invalid JSON file: %s, throws exception: %s\n", m_regexPath.c_str(), iaException.what());
         return false;
     }
@@ -83,7 +83,7 @@ bool RsyslogPlugin::createRegexList() {
             rs.tag = tag;
             rs.regexExpression = expression;
             regexList.push_back(rs);
-	} catch (domain_error& deException) {
+	} catch (nlohmann::detail::type_error& deException) {
             SWSS_LOG_ERROR("Missing required key, throws exception: %s\n", deException.what());
             return false;
         } catch (regex_error& reException) {

src/sonic-eventd/rsyslog_plugin/syslog_parser.h

@@ -11,7 +11,7 @@ extern "C"
 #include <vector>
 #include <string>
 #include <regex>
-#include "json.hpp"
+#include <nlohmann/json.hpp>
 #include "events.h"
 #include "timestamp_formatter.h"
 

src/sonic-eventd/rsyslog_plugin_tests/rsyslog_plugin_ut.cpp

@@ -9,7 +9,7 @@ extern "C"
 #include <memory>
 #include <regex>
 #include "gtest/gtest.h"
-#include "json.hpp"
+#include <nlohmann/json.hpp>
 #include "events.h"
 #include "../rsyslog_plugin/rsyslog_plugin.h"
 #include "../rsyslog_plugin/syslog_parser.h"

src/sonic-eventd/tools/events_tool.cpp

@@ -1,4 +1,5 @@
 #include <thread>
+#include <iostream>
 #include <stdlib.h>
 #include "events.h"
 #include "events_common.h"