AssociativeAlgebras: failure to lift to coefficient ring

This doesn't work
```
i1 : needsPackage"AssociativeAlgebras";

i2 : R=QQ<|x|>;

i3 : m=matrix{{1_R}}

o3 = | 1 |

1 1
o3 : Matrix R <-- R

i4 : lift(m,QQ)
stdio:4:4:(3): error: expected each multidegree to be of length 0
```
to be compared with
```
i1 : R=QQ[x];

i2 : m=matrix{{1_R}}

o2 = | 1 |

1 1
o2 : Matrix R <-- R

i3 : lift(m,QQ)

o3 = | 1 |

1 1
o3 : Matrix QQ <-- QQ
```
See also #3155 for why one might want to lift...

Reproduce the failure in the Macaulay2 REPL using the AssociativeAlgebras example, then compare it with the working QQ[x] case. Start by tracing the AssociativeAlgebras package's lift path; done means lift(m,QQ) succeeds for the coefficient ring and returns a Matrix QQ as shown.

Written by the indexing model from the issue text.