Insert a missing word

This phrase part was missing the «it» word as a subject.

New lines were reorganized a bit in order to respect the 80 character
wrap length.
minor #4278 Missing word in DependencyInjection => Types of Injection (fabschurt)

This PR was merged into the 2.3 branch.

Discussion
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Missing word in DependencyInjection => Types of Injection

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | 2.3+
| Fixed tickets | n/a

Commits
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2377280 Insert a missing word