[C][Client] Convert integer/boolean to string for query parameter in request url

Created by: ityuhui

If the data type of query parameter is "int" or "bool" in OpenAPI Spec, the request url will not be right generated by c-libcurl.

For example, in the function

CoreV1API_listNamespacedPod(..., int limit ,... )
{
...
    // query parameters
    char *keyQuery_limit = NULL;
    int valueQuery_limit ;
    keyValuePair_t *keyPairQuery_limit = 0;
    if (limit)
    {
        keyQuery_limit = strdup("limit");
        valueQuery_limit = (limit);
        keyPairQuery_limit = keyValuePair_create(keyQuery_limit, &valueQuery_limit);  <-- limit is only be referred as int *
        list_addElement(localVarQueryParameters,keyPairQuery_limit);
    }

but in the function

char *assembleTargetUrl(char    *basePath,
                        char    *operationParameter,
                        list_t    *queryParameters) {
    if(queryParameters != NULL) {
        strcat(targetUrl, "?");
        list_ForEach(listEntry, queryParameters) {
            keyValuePair_t *pair = listEntry->data;
            replaceSpaceWithPlus(pair->key);
            strcat(targetUrl, pair->key);
            strcat(targetUrl, "=");
            replaceSpaceWithPlus(pair->value);
            strcat(targetUrl, pair->value);    <=== valueQuery_limit is not a char *, so this is wrong.
            if(listEntry->nextListEntry != NULL) {
                strcat(targetUrl, "&");
            }
        }
    }

If we call

CoreV1API_listNamespacedPod(...
                                           10,   /* limit */
...);

the targetUrl becomes:

"https://ip:6443/api/v1/namespaces/default/pods?limit=P.xUUU"

My fix is converting the parameter to string

    // query parameters
    char *keyQuery_limit = NULL;
    char * valueQuery_limit = NULL;
    keyValuePair_t *keyPairQuery_limit = 0;
    if (limit)
    {
        keyQuery_limit = strdup("limit");
        valueQuery_limit = calloc(1,MAX_NUMBER_LENGTH);
        snprintf(valueQuery_limit, MAX_NUMBER_LENGTH, "%d", limit);
        keyPairQuery_limit = keyValuePair_create(keyQuery_limit, valueQuery_limit);
        list_addElement(localVarQueryParameters,keyPairQuery_limit);
    }

the targetUrl now is right:

"https://ip:6443/api/v1/namespaces/default/pods?list=10"

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