[ci] Add spell check · RT-Thread/rt-thread@8376eda

Spell check: README_de.md#L17

ist ==> is, it, its, it's, sit, list

Spell check: README_de.md#L19

ist ==> is, it, its, it's, sit, list

Spell check: README_de.md#L19

ist ==> is, it, its, it's, sit, list

Spell check: README_de.md#L25

ist ==> is, it, its, it's, sit, list

Spell check: README_de.md#L31

Sie ==> Size, Sigh, Side

Spell check: README_de.md#L33

Semaphor ==> Semaphore

Spell check: README_de.md#L33

ist ==> is, it, its, it's, sit, list

Spell check: README_de.md#L37

oder ==> order, older, coder, odder, odor, over, doer

Spell check: README_de.md#L37

oder ==> order, older, coder, odder, odor, over, doer

Spell check: README_de.md#L37

ist ==> is, it, its, it's, sit, list

Spell check: libcpu/arm/sep4020/start_rvds.S#L1