Up the max connectionCount to 200

Have seen defects where hitting the max connection limit with multiple
server managers attached. Although not common to exceed 100, can hit
this when using 2 or 3 webui-vue GUIs and a server manager attached.
webui-vue can use ~30 of these on its own; this isn't that hard to hit.

Nginx by default sets 512 connections[1] , so 200 for an embedded
target doesn't seem that unreasonable:

Apache sets 256 by default [2]

lighttpd sets 1024 [3]

We're in line for the defaults for other webservers.

Tested: Sent 180 basic auth requests seen bmcweb memory at
 2189  2178 root     R    29080   4%  49% ./bmcweb
This was on a AST2600 (p10bmc)

The connections open got to:
[DEBUG "http_connection.hpp":79] 0x19bb5c8 Connection open, total 161

Came back down as expected:
[DEBUG "http_connection.hpp":89] 0x1a41440 Connection closed, total 1

Didn't see this with multiple webui-vues / server managers.

[1] https://nginx.org/en/docs/ngx_core_module.html#worker_connections
[2] https://httpd.apache.org/docs/2.4/mod/mpm_common.html#maxrequestworkers
[3] https://redmine.lighttpd.net/projects/1/wiki/Server_max-connectionsDetails

Change-Id: I807302e32e61e31212850a480d721d89d484593f
Signed-off-by: Gunnar Mills <gmills@us.ibm.com>
diff --git a/http/http_connection.hpp b/http/http_connection.hpp
index d60e74b..83645ee 100644
--- a/http/http_connection.hpp
+++ b/http/http_connection.hpp
@@ -158,7 +158,7 @@
 
     void start()
     {
-        if (connectionCount >= 100)
+        if (connectionCount >= 200)
         {
             BMCWEB_LOG_CRITICAL("{}Max connection count exceeded.",
                                 logPtr(this));