Writing a test for the /blog/update endpoint

[jwoolbright23]

Is your feature request related to a problem? Please describe.
The /blog/update endpoint is in need of a unit test.

Describe the solution you'd like
Write a test that successfully updates already existing information inside of the database to something new.

Additional context
This is a test written inside of BlogTests.Java to test the @PostMapping /blogs endpoint.

@Test
	public void postBlogs_SavesBlogToDatabase() throws Exception {
		blogTestsUtil.tearDown();
		Blog blog1 = new Blog("Our Very First Blog Post", "This is an actual Subheader", "An Actual Image", "This body has things we actually care about");
		MockMultipartFile firstFile = new MockMultipartFile("image", "filename.txt", "text/plain", "some xml".getBytes());
		MvcResult result = mockMvc.perform(multipart("/blogs").file(firstFile).param("blogData", objectMapper.writeValueAsString(blog1)))
				.andDo(print())
				.andExpect(status().isOk())
				.andExpect(jsonPath("$.header").value("Our Very First Blog Post"))
				.andReturn();
		assertEquals(1, blogRepository.findAll().size());
		blogTestsUtil.tearDown();
	}