Fix technical debt cause by Merge Request Notes refactor
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While debugging the code added here https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#3ce7f1dd43287a1d04e957283a8f7ff4e3f60ec3_80_93
I found the following problems:
1. `camelCaseKeys` function is duplicated and is not used. This was pointed in the MR, but somehow was merged. Fixed in: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/17667
1. Sprintf with user generated content needs to be escaped: https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#e75a068a217e33deac9009c31c835d7b972d2210_67_79
1. Do i18n properly:https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#note_62474836
1. `v-html` shouldn't be used:
1. https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#d63222f7e9a4ec7b560a9e43597e4de7c2e4fffc_0_32
1. https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#note_62474886
1. Identation doesn't follow the styleguide: https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#3e9f352f8d1d561f5108008cbec308921f6eb9d5_0_82
1. SVGs should use `icon.vue`: https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#a8841151b538089b177018118015a54d494223a3_0_45
1. A span with `type=button` https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#a8841151b538089b177018118015a54d494223a3_0_77
1. a class named `.line-resolved-text`: https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#a8841151b538089b177018118015a54d494223a3_0_77
1. button without type: https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#note_62474218
1. Unecessay reassignment https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#note_62474165
1. Button without type https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#d7023f611ef2e7cf7310e5813e81acb8bf38ed6f_171_184
1. loading_icon.vue should have been used https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#note_62476132
1. icon.vue should have been used: https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#note_62476218
1. no button type https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#note_62476243
1. Unresolved fixme comment: https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#note_62476357
1. foreach was used instead of reduce. Decreases performance & readability: https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#note_62473611
1. Improve variable naming: https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#note_62476577
1. what is this foreach doing? https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#note_62473672
1. component order is not the same as the styleguide: https://gitlab.com/gitlab-org/gitlab-ce/commit/059ab73b8eae3a546d0a19fe99ef0c52df5fac01#5ff60f23cdeb24af173d741ad2c3373aa3b23d35_0_1
issue