NullPointerException is thrown when pagination headers are missing

[andacata]

When the required headers X-Total-Count or X-Limit are not returned from the other partner, an uncontrolled NullPointerExeption is thrown.

ocpi-toolkit/ocpi-toolkit-2.2.1/src/main/kotlin/com/izivia/ocpi/toolkit/common/HttpUtils.kt

Lines 56 to 61 in 0230204

	data = parsedBody.data?.toSearchResult(
	totalCount = getHeader(Header.X_TOTAL_COUNT)!!.toInt(),
	limit = getHeader(Header.X_LIMIT)!!.toInt(),
	offset = offset,
	nextPageUrl = getHeader(Header.LINK)?.split("<")?.get(1)?.split(">")?.first()
	),

[lilgallon]

It is a more general issue, see #17

We should do that everywhere it's needed. But it is a good start